precision electronic solutions CODE SCANNER¨ FAVOR DE LEER INSTRUCTCTIVO ANTES DE USAR EL ARTICULO Car Computer Code Reader Domestic GM & Saturn Lector de Códigos de Computadoras de Automóvil GM y Saturn nacionales de EE.UU.
CP9001 ™ CONTENTS Congratulations on purchasing your Actron Code Scanner for accessing engine trouble codes required for repairing vehicles equipped with computers. Your Actron Code Scanner is made by Actron, the largest and most trusted name in automotive diagnostic equipment for the home mechanic. You can have confidence this product maintains the highest quality in manufacturing, and will provide you years of reliable service. This instruction manual is divided into several key sections.
General Safety Guidelines to follow when working on vehicles • Always wear approved eye protection. • Always operate the vehicle in a well ventilated area. Do not inhale exhaust gases – they are very poisonous! • Always keep yourself, tools and test equipment away from all moving or hot engine parts. • Always make sure the vehicle is in park (Automatic transmission) or neutral (manual transmission) and that the parking brake is firmly set. Block the drive wheels.
About Codes Where do they come from and what are they for? Engine computers can find problems. available from the manufacturer, other publishers or your local public library. (See Vehicle Service Info on page 4.) The computer system in today’s vehicles does more than control engine operation – it can help you find problems, too! Special testing abilities are permanently programmed into the computer by factory engineers.
Trouble codes give you valuable knowledge – whether you go for professional vehicle servicing or “do-ityourself. ” Now that you know what trouble codes are and where they come from, you are well on your way to fixing today’s computer controlled vehicles! Vehicle Service Information The following is a list of publishers who have manuals containing trouble code repair procedures and related information. Some manuals may be available at auto parts stores or your local public library.
When to Read Codes Use the Code Scanner to read computer trouble codes if... Check Engine Light: Problem Spotted! • The “Check Engine” light comes ON when the engine is RUNNING or, • Vehicle engine is running poorly and “Check Engine” light is OFF. Light ON and stays ON (when the engine is RUNNING) – The computer sees a problem that does not go away. (A “hard” failure.) – The light will stay on as long as the problem is present. – A trouble code is stored in computer memory. (A “hard” code.
Reading Codes Using the Code Scanner to Read Codes 1) Safety First! • Set the parking brake. • Put shift lever in PARK (automatic transmission) or NEUTRAL (manual transmission). • Block the drive wheels. • Make sure ignition key is in OFF position. • The connecter is located under the dashboard on the driver’s side. Exceptions: –LeMans: Located behind passenger side kick panel. Remove snapon cover for access. –Fiero: Located in the center console behind cover panel.
6) Plug the Code Scanner into the Test Connector. Put TEST switch on ENGINE. sequence is repeated. This continues until the ignition key is turned OFF (so you can double check your code list). Example of code 12 only: Ca GM rC 198 om 2& pu hig ❊ PAUSE ❊❊ ter her Co -C de P9 Re 001 ad FLASH (pause) FLASH FLASH (longer pause) TM er ❊ PAUSE ❊❊ • The Code Scanner only fits ONE WAY into the test connector. • The Code Scanner will not harm the vehicle engine computer.
• A code 12 is always sent even when the computer sees no problem. This tells you the computer diagnostic checks are working properly. If you do not get a code 12, or if the “Check Engine” light does not flash you have a problem which must be repaired. Refer to “Diagnostic Circuit Check” procedure in vehicle service manual. (See manual listing on page 4.) • All codes are two (2) digits long. • Codes are sent in numeric order from the lowest number to the highest.
TEST RESULTS COMMENTS No indication on “Check Engine” light or, Did not receive Code 12. • You have a problem which needs repair before using the Code Scanner. Code 12 only. • Computer did NOT find a problem. • Refer to “Diagnostic Circuit Check” chart in vehicle service manual. • If a driveability problem persists, perform “Visual Inspection” and “Basic Mechanical Checks” (Section 4, “Using Codes”.) • Refer to “Diagnosis by Symptom” charts in vehicle service manual.
Using Codes Using Trouble Codes as Part of a Basic Troubleshooting Procedure A driveability problem can have many possible causes which are not related to the computer system. Reading codes is one part of a good troubleshooting procedure consisting of: 1) Visual Inspection 2) Basic Mechanical Checks 3) Reading Codes 4) Using the Vehicle Service Manual 5) Erasing Codes Information YST (VECI) G GAP decal U.S.A. located in the engine compartment. –Pinches and kinks. –Splits, cuts or breaks.
2) Basic Mechanical Checks • “Hard” codes – codes for problems which are present now. • “Intermittent” codes – codes for problems which happened in the past, but are not happening now. Remember... –“Check Engine” light ON: You have at least one “hard” code stored in memory. (You may have more “hard” or “intermittent” codes stored, also.) – “Check Engine” light OFF: Stored codes are for “intermittent” problems.
• • • – called “Computerized Engine Controls”, “Electronic Engine Controls” or “Tune-Up Information.” Follow all the steps in the diagnostic procedure for the trouble code. Be sure to erase the trouble codes from computer memory after completing repair work. (See Step 5, “Erasing Codes from Computer Memory”.) Drive vehicle for at least 10 minutes at normal temperature, cruise speed and load. Read codes again to verify trouble code is gone (problem fixed).
SATURN –Open the in-line fuse holder going to the positive battery terminal, OR Use the GM method, or proceed as follows: • Observe all safety precautions. (See page 2.) Warning: Stay away from the engine cooling fan. It may turn on during this procedure. –Disconnect negative battery terminal – but this will also erase other items too, such as digital clock settings and preset digital radio tuning. • All the trouble codes are now erased from computer memory! • Wait thirty (30) seconds.
Code Meanings Note: Remember: • Code meanings can vary with vehicle, model year, engine type and options. • If a code number has more than one definition listed, note that that only one definition applies to your vehicle. Consult service manual to get the specific definition and troubleshooting procedure for your vehicle. • Follow vehicle service manual procedures to find the cause of the code.
21 Throttle position sensor (TPS) - signal voltage is high during engine idle or deceleration. 22 Throttle position sensor (TPS) - signal voltage is low during engine idle. OR Fuel cutoff relay circuit open or shorted to ground. 23 Manifold air temperature (MAT) sensor - signal voltage is low or high. OR Throttle position sensor (TPS) error. OR Mixture Control (M/C) solenoid - open or short circuit problems. 24 Vehicle speed sensor (VSS) - open or short circuit problems.
41 Cam sensor (CAM) failure. OR Cylinder select error. OR Tach input error - no reference pulses during engine run. OR Electronic spark timing (EST) circuit - open or shorted to ground during engine run. OR Direct ignition system (DIS) fault - bypass circuit open or shorted to ground during engine run. OR Ignition system fault - loss of 1X Reference Pulse signal. 42 Electronic spark timing (EST) circuit - open or shorted to ground during engine run.
61 Oxygen (O2) sensor degraded. OR Port throttle system error. OR Cruise control problems vent solenoid circuit. OR Air Conditioner (A/C) system performance problems. 62 Gear switch circuit problems. OR Oil temperature sensor signal voltage is high (Corvette). OR Cruise control problems vacuum solenoid circuit. 63 Manifold absolute pressure (MAP) sensor - signal voltage is high. OR Small EGR failure. OR Right oxygen (O2) sensor failure (dual sensor engines). OR Cruise control system problem.
81 Brake switch circuit problems. OR Anti-Lock Brake System (ABS) message fault (Saturn). OR (Transmission) Solenoid “B” (3-2 shift solenoid) open or short circuit problems. 82 Ignition system fault - 3X signal problem. OR Electronic control module (ECM) computer circuit problem - internal communications failure (Saturn). OR (Transmission) Solenoid “A” (1-2 shift solenoid) open or short circuit problems. 83 Torque Converter Clutch (TCC) solenoid - circuit problems.
Saturn Transmission Codes (GM/Saturn engine codes and GM transmission code list begins on page 14.) Note: Code numbers labeled “Information Flag” may be sent along with the regular (unlabeled) trouble codes. The computer sends Information Flags to help you find the cause of a trouble code. Note that conditions which only cause an Information Flag will not turn on the “Check Engine” light. Refer to vehicle service manual troubleshooting charts.
absolute pressure (MAP) sensor signal, handwheel sensor signal, throttle position sensor (TPS) signal are zero volts. 55 Transaxle temperature sensor failure. 56 63 71 Powertrain Control Module (PCM) computer circuit problem - Random Access Memory (RAM) failure. OR 2nd line circuit - grounded or open. OR (Information Flag) (Information Flag) Generic Field-Effect Transistor (FET) driver failure.
76 83 92 4th line circuit - grounded or open. OR Transaxle temperature low. OR Clamp circuit - intermittent fault. (Information Flag) (Information Flag) Throttle position sensor (TPS) to manifold absolute pressure (MAP) sensor voltage out of range - flag is set if TPS and MAP voltage readings dont agree with internal relational tables stored in the powertrain control module (PCM). Low coolant - coolant switch opens for 20 seconds with engine running.
Other Features Additional Code Scanner Diagnostic Features This section contains... Relay and Solenoid Circuit Test: You can switch on most of the computer controlled relay and solenoid circuits for checking relay operation or making wiring voltage checks. Field Service Test (Fuel Injected Engines Only): A quick check of the fuel control system to verify proper operation. Become familiar with Code Scanner use (Section 3) before using the following procedures. “driver”).
Field Service Test Fuel Injected Engines Only 3) Turn Ignition Key to ON Position but DO NOT START THE ENGINE. • WARNING: Stay away from the radiator cooling fan! It may turn on. • Ignore the flashing Check Engine light. This is a quick check of the fuel control system to verify proper operation especially after repair work. Service manuals call this the “Field Service Mode”. Do the following: 4) Computer Controlled Relays and Solenoids are Turned ON Exception: Fuel pump and fuel injectors are OFF.
• Light mostly ON while flashing: system is running “rich”. • Light mostly OFF while flashing: system is running “lean”. Various mechanical, electronic or wiring problems can cause the computer to sense a “rich” or “lean” running engine. Usually these conditions will generate a trouble code, such as 44 (lean exhaust) or 45 (rich exhaust). Follow vehicle service manual troubleshooting charts to find the cause. The Field Service Test lets you check to see if the problem was fixed.
COMPUTER BASICS What does the Engine Control Computer do? What has NOT changed? This section further explains the engine computer control system, the types of sensors and how the computer controls fuel delivery, idle speed and timing. The following is an introduction to computer controlled engine systems. Additional information may be found in books dealing with this subject available at your local library or auto parts store.
(voltage signal to the computer) or OFF (no voltage signal to the computer). Switches connect to two wires and tell the computer simple things, such as whether or not the air conditioner is running. BRAINS OF THE COMPUTER O AC UT TU P AT UT OR S UT INP SORS SEN • Signal Generator – These create their own signal to tell the computer of some condition, such as exhaust gas oxygen content, camshaft position, or intake manifold vacuum. They may have one, two or three wires connected to them. can understand.
The computer needs to know: • ...what the engine operating condition is. Sensors used: coolant temperature, throttle position, manifold absolute pressure, mass air flow, RPM. • ...how much air is coming into the engine. Sensors used: mass air flow or a combination of manifold absolute pressure, manifold air temperature, RPM. • ...how much fuel is being delivered. The computer knows this by how long it turns on the fuel injectors.
Acceleration, deceleration and idle conditions How the computer controls spark advance timing As long as the engine and oxygen sensor are hot, the computer can operate “closed loop” for best economy and least emissions. During the drive conditions listed on the left, the computer may have to ignore the sensor and run “open loop,” relying on internal programming for fuel delivery instructions. During idle, for example, the oxygen sensor may cool down and stop sending a signal.
Computer controlled emission systems Other computer functions EGR (Exhaust Gas Recirculation) Valve The computer often controls various other functions around the vehicle. Detailed explanations may be found in your vehicle service manual. Some typical examples are... The EGR valve lets exhaust gases reenter the intake manifold and mix with the incoming air/fuel. The presence of exhaust gases reduces combustion temperatures in the cylinders and this reduces poisonous NOx emissions.
vehicle speed, engine loading and other sensor information to determine the optimum shift performance. The computer can also set the shift quality - anywhere from harsh to smooth. This is done using a “force motor” actuator in the transmission to adjust the internal fluid line pressure. conditions. This improves fuel economy by eliminating power loss in the torque convertor. The computer energizes a solenoid to achieve lockup.
GLOSSARY A/C Air conditioner. solenoids and motors. Actuators allow the ECM to control engine operation. A/C Clutch relay A/F The ECM uses this relay to energize the A/C clutch - to turn the A/C system on or off. A/C On (A/C Signal) An input signal to the ECM indicating that either the A/ C compressor is running or that A/C operation is being requested (depends upon vehicle). Then ECM adjusts idle speed to prevent engine stalling when the A/C system is engaged.
C3 Computer Command Control. The name for the GM electronic engine control system used on most vehicles built since 1982. Thus, closed loop operation means the ECM can “fine tune” control of a system to get an exact result providing the ECM has a sensor (or other means) to check results. CALPAK Continuity A “spare tire” for the ECM. It is circuitry which can operate the vehicle fuel injectors in a limited fashion should the ECM malfunction. The CALPAK is hidden behind an access door on the ECM.
(Digital Multi-Meter). Most DVM’s have 10 Megohm input impedance. This means the circuit under test will not be electronically disturbed when the DVM is connected for a measurement. ECM Electronic Control Module. The “brains” of the engine control system. It is a computer housed in a metal box with a number of sensors and actuators connected with a wiring harness. Its job is to control fuel delivery, idle speed, spark advance timing and emission systems.
delivery modified by an electronic signal from the ECM. The signal controls a “mixture control solenoid” (MCS) attached to the carburetor body. Frequency The frequency of an electronic signal is a measure of how often the signal repeats a voltage pattern in a one second time span. For example: suppose a signal starts at zero volts, goes to five volts then returns to zero again. If this pattern repeats itself 100 times in one second, then the signal frequency is 100 cycles per second - or 100 Hertz.
Inputs Electrical signals running into the ECM. These signals come from sensors, switches or other electronic modules. They give the ECM information about vehicle operation. ISC Idle Speed Control. This refers to a small electric motor mounted on the throttle body and controlled by the ECM. The ISC motor moves a spindle back and forth. When the throttle is released during idle, it rests on this spindle. The ECM can control idle speed by adjusting this spindle position.
P/N Park/Neutral switch. This switch tells the ECM when the gear shift lever is in the Park or Neutral position. Then the ECM will operate the engine in an “idle” mode. Pressure Control solenoid This solenoid is located inside certain automatic transmissions. The ECM uses this solenoid to vary the internal line pressure, as required, based on engine load condition PROM Programmable Read-Only Memory. A small, replaceable electrical component hidden behind an access door on the ECM.
Stepper Motor A special type of electric motor with a shaft that rotates in small “steps” instead of a continuous motion. A certain sequence of frequency type signals is required to step the motor shaft. A different signal sequence will step the shaft in the opposite direction. No signals keeps the shaft still in position. A constant signal drive will continuously rotate the shaft.
ABS BASICS A General Description of ABS Systems The ABS System The following is an overview of AntiLock Brake Systems (ABS). There are several different types and versions. Refer to vehicle service manual for specific details. IMPORTANT: To service ABS systems safely and effectively, you must obtain a service manual for your vehicle and carefully follow all procedures.
ABS Types wheels. The hydraulic portion is the same as the 3 Channel system. The ABS computer uses a three channel Hydraulic Control Modulator to control the right front wheel, the left front wheel and both rear wheels. There are three basic types... • RWAL (Rear Wheel Anti-Lock) This is the simplest ABS system (mostly used on small rear-wheel-drive trucks). Only the rear wheels are ABS controlled – not the front.
is usually mounted close to the master Magnet Teeth Sensor cylinder. (Some ring systems combine the Wire Coil To hydraulic control computer S N modulator and the master cylinder into Air one complete unit.) gap The valves are Rotation connected in the brake lines between the Typical Front Sensor Typical Rear Sensor master cylinder and Axle the wheel caliper (or Hub and rotor housing wheel cylinder).
brake circuit during ABS operation. (ABS relieves brake line pressure to avoid wheel lock-up.) Four wheel ABS systems use two accumulators: one for the rear wheel circuit and the other for the front wheel circuit. The accumulator contains a moveable diaphragm which separates the inside into two chambers. One chamber collects the hydraulic fluid. The other side contains a spring pressing against the diaphragm. Because of the spring, accumulator hydraulic pressure is about 150 PSI.
– continuously monitor wheel speed or... – wait for brake pedal application before monitoring wheel speed. The ABS computer controls braking action when wheel speed acceleration or deceleration indicates lock-up is about to occur. Four-Wheel Drive Vehicle Note: The ABS computer will not allow ABS braking during four-wheel drive operation. (A switch in the four-wheel drive powertrain sends a signal to the ABS computer.
ABS Braking – Pressure Increase Wheel speed signals indicate absence of lock-up condition. ABS computer takes last step in brake control cycle: increase hydraulic pressure to wheel caliper/cylinder. ABS Braking – Pressure Decrease Wheel speed signals indicate lock-up is still about to occur. ABS computer takes next step in brake control cycle: decrease hydraulic pressure to wheel caliper/cylinder.
ABS SAFETY General Safety Guidelines to Follow When Working on ABS Vehicles WARNING: To avoid personal injury, DO NOT open a bleeder valve or loosen a hydraulic line while ABS is pressurized. Always follow vehicle manufacturer’s procedures to depressurize ABS before servicing. • Always use specially designed ABS brake hoses and fittings when replacing these parts. • Always use ABS recommended brake fluids. DO NOT use silicone brake fluids in ABS systems. • Always wear approved eye protection.
ABS TIPS Useful Hints to Know When Troubleshooting ABS Systems IMPORTANT: Always follow vehicle service manual procedures for any ABS repairs. (Manual listings on page 4.) • Do a thorough visual and “hands-on” inspection first. You can often find the cause of many problems by just looking. • Radio transmitters can interfere with operation of ABS computer. Keep antenna wiring from a CB radio or portable telephone away from ABS wiring • ABS systems rely on accurate wheel sensor signals.
needed, from your vehicle dealer. It is a special type for this purpose. • Make sure any recommended system flushing has been performed. Corrosion or dirt in ABS valving can result in poor pedal performance. • Some body and chassis work procedures can harm the ABS computer: – Disconnect vehicle computer modules when using electric welding equipment. – Do not expose the ABS computer to high heat for a long time (for example, during vehicle painting).
READING CODES How to Use the Code Scanner to Read ABS Codes 1) Use the chart to find the ABS system used on your vehicle. 2) Refer to the page listed where you will find... • preliminary checks you need to make before reading codes, • the code reading procedure, • the procedure for erasing codes from ABS computer memory, • a list of code definitions.
1990 Model System 98 Regency Astro 5 1991 Page Model 74 7 or 8 See note p. 50 System Page Astro 7 or 8 See note p. 50 Blazer 7 or 8 See note p.
1992 Model System 1993 Page Model Astro 7 or 8 See note p. 50 Astro Blazer 7 or 8 See note p. 50 Blazer Bravada 8 88 Bravada Brougham 2 56 C Series Pickup Truck C Series Pickup Truck 7 or 8 See note p. 50 Eldorado 3 62 G Series (RWD) Van 7 84 Jimmy K Series Pickup Truck Riviera 7 or 8 See note p. 50 3 S Series Pickup Truck 7 or 8 See note p. 50 Safari 7 or 8 See note p. 50 Seville Sierra Sonoma Suburban Syclone T Series Pickup Truck 3 8 88 Jimmy 7 or 8 See note p.
1994 Model Astro Blazer Bravada C Series Pickup Truck System 8 Page 88 7 or 8 See note below 8 88 7 or 8 See note below DeVille 4 68 Eldorado 4 68 G Series Van 8 88 Jimmy 8 88 K Series Pickup Truck 7 or 8 See note below S Series Pickup Truck 7 or 8 See note below Safari 8 88 Seville 4 68 Sierra 8 88 Sonoma 8 88 Suburban 8 88 T Series Pickup Truck Yukon 7 or 8 See note below 8 88 NOTE: Two different ABS systems were available for this vehicle.
SYSTEM 1: Bosch 2S 1990 Corvette 1991 Corvette Functional Check Corvette Pre-Diagnostic Visual Inspection Complete all steps before reading trouble codes! 1) Start the engine. The brake warning lamp should come ON during engine cranking, and turn OFF shortly after the engine starts. If it does not, check the brake warning lamp circuit in accordance with vehicle service manual instructions.
Reading ABS Codes Bosch 2S 6) Plug the Code Scanner into the test connector • The Code Scanner only fits ONE WAY into the test connector. • The Code Scanner will not harm the vehicle computer. Note: The Code Scanner does not use all of the test connector contacts. This is normal. IMPORTANT: Perform all steps in PRE-DIAGNOSTIC VISUAL INSPECTION and FUNCTIONAL CHECK before reading ABS codes! Ca GM 1) Take Safety Precautions • Set parking brake, block drive wheels.
Example of code 12 only: • A code 12 is always sent even when the computer sees no problem. This tells you the computer diagnostic checks are working properly. • All codes are two (2) digits long. ❊ PAUSE ❊❊ FLASH (pause) FLASH FLASH (longer pause) ❊ PAUSE ❊❊ 9) Turn Ignition Key OFF FLASH (pause) FLASH FLASH (longer pause) ❊ PAUSE 10)Remove Code Scanner and Reinstall Connector Cover, if supplied The computer system is now back to normal operation.
Erasing ABS Codes from Computer Memory Bosch 2S 3) Wait 15 seconds, then observe the anti-lock indicator lamp. Code 12, the “diagnostic system operational” code should flash indicating that all trouble codes have been erased from memory. Turn the ignition FF ON switch to the OFF position. Remove the Code Scanner, and reinstall the test connector cover (if used on vehicle). 1) Turn the ignition switch to the OFF position.
ABS Code Meanings Bosch 2S IMPORTANT: Always follow vehicle service manual procedures for any ABS repairs! (Manual listings on page 4.) 12 Diagnostic System Operational. 21 Right Front Wheel Speed Sensor circuit. Checks for open, shorted or intermittent condition in subject circuit. Vehicle speed must be equal to or greater than 4 MPH for this code to set. 22 Right Front Toothed Wheel Frequency Error. Checks for excessively dirty, or damaged toothed wheel (sensor ring).
SYSTEM 2: Bosch 2U (Version A) 1990 Brougham 1991 Caprice, Custom Cruiser, Roadmaster 1992 Brougham Pre-Diagnostic Visual Inspection • 1990 Brougham: –Check the GA-TRANS fuse in the underdash fuse block. –Check the ABS fuse in the underdash fuse block. –Check the STOP/HAZ fuse in the underdash fuse block. –Check the rust colored fusible links on the positive junction block. Complete all steps before reading trouble codes! 1) Check that all ABS system grounds are clean and tight.
3) Drive the vehicle at least 20 MPH. If the anti-lock lamp turns ON, proceed to READING ABS CODES. Perform FUNCTIONAL CHECK before reading codes! Functional Check Reading ABS Codes: Bosch 2U (Version A) Brougham 1) Start the engine. The brake warning lamp should come ON during engine cranking, and turn OFF shortly after the engine starts. If it does not, check the brake warning lamp circuit in accordance with vehicle service manual instructions. 2) Turn the engine OFF.
Code 12 looks like: testing. Some vehicles require this cover in place for proper operation. ❊ PAUSE ❊❊ FLASH (pause) FLASH FLASH (FLASH = 1, FLASH FLASH = 2. Put 1 and 2 together = code 12.) O 4) Verify Ignition Key is OFF FF ON TEST ABS ENGINE Code 23 looks like: ❊❊ PAUSE ❊❊❊ 5) Put the TEST switch on ABS FLASH FLASH (pause) FLASH FLASH FLASH • Each code is flashed three (3) times before the next trouble code is sent. • After all codes are sent, the whole sequence is repeated.
Example of code 12 only: • A code 12 is always sent even when the computer sees no problem. This tells you the computer diagnostic checks are working properly. • All codes are two (2) digits long.
Erasing ABS Codes from Computer Memory: Bosch 2U (Version A) 3) Remove the Code Scanner for about 1 second then reinstall Code Scanner into the connector. Repeat this procedure 4 times within 10 seconds. Leave the Code Scanner inserted in the connector after the 4th time. Car GM Erase codes from memory whenever you complete a repair or to see if a problem will occur again. Note: The computer will automatically erase codes after several restarts (typically 100) if the problem does not return.
ABS Code Meanings: Bosch 2U (Version A) IMPORTANT: Always follow vehicle service manual procedures for any ABS repairs! (Manual listings on page 4.) 12 Diagnostic System Operational. This code is always sent. 21 Right Front Wheel Speed Sensor circuit. Checks for open, shorted or intermittent condition in subject circuit. Vehicle speed must be equal to or greater than 4 MPH for this code to set. 22 Right Front Toothed Wheel Frequency Error.
SYSTEM 3: Bosch 2U (Version B) 1991 Brougham, Eldorado, Reatta, Riviera, Seville, Toronado, Trofeo 1992 Eldorado, Riviera, Seville, Toronado, Trofeo 1993 Riviera Pre-Diagnostic Visual Inspection –Check the ABS fuse in the underdash fuse block. –Check the rust colored fusible link E on the positive junction block. Complete all steps before reading trouble codes! • 1991 Eldorado, Seville: –Check fuse number 7 in the interior relay center.
Functional Check • 1992 Toronado, Trofeo: –Check fuse number 18 in the underdash fuse block. –Check the black and blue colored fusible links on the positive junction block. 1) Start the engine. The brake warning lamp should come ON during engine cranking, and turn OFF shortly after the engine starts. If it does not, check the brake warning lamp circuit in accordance with vehicle service manual instructions. • 1993 Riviera: –Check fuse number 4 in the interior relay center.
Reading ABS Codes: Bosch 2U (Version B) 5) Put the TEST switch on ABS IMPORTANT: Perform all steps in PRE-DIAGNOSTIC VISUAL INSPECTION and FUNCTIONAL CHECK before reading ABS codes! TEST ABS ENGINE Car GM Com 1982 pute & hi r Cod gher e R - CP eade 9001 r TM 6) Plug the Code Scanner into the test connector • The Code Scanner only fits ONE WAY into the test connector. • The Code Scanner will not harm the vehicle computer. Note: The Code Scanner does not use all of the test connector contacts.
Example of code 12 only: • A code 12 is always sent even when the computer sees no problem. This tells you the computer diagnostic checks are working properly. • All codes are two (2) digits long.
Erasing ABS Codes from Computer Memory: Bosch 2U (Version B) 3) Without turning the ignition switch OFF, repeat the sequence outlined in Step 2, 2 more times. Erase codes from memory whenever you complete a repair or to see if a problem will occur again. Note: The computer will automatically erase codes after several restarts (typically 100) if the problem does not return.
ABS Code Meanings: Bosch 2U (Version B) IMPORTANT: Always follow vehicle service manual procedures for any ABS repairs! (Manual listings on page 4.) 12 Diagnostic System Operational. This code is always sent. 21 Right Front Wheel Speed Sensor circuit. Checks for open, shorted or intermittent condition in subject circuit. Vehicle speed must be equal to or greater than 4 MPH for this code to set. 22 Right Front Toothed Wheel Frequency Error.
SYSTEM 4: Bosch 2U (Version C) 1993 Eldorado, Seville 1994 DeVille, Eldorado, Seville Pre-Diagnostic Visual Inspection 3) Check that all ABS/TCS connectors, and EBTCM (Electronic Brake and Traction Control Module) connectors are properly installed (not loose). Complete all steps before reading trouble codes! 1) Check that all ABS system grounds are clean and tight. –Check the ground that is located on the bottom left side of the engine block, near the transaxle.
Reading ABS Codes: Bosch 2U (Version C) 5) Put the TEST switch on ABS IMPORTANT: Perform all steps in PRE-DIAGNOSTIC VISUAL INSPECTION and FUNCTIONAL CHECK before reading ABS codes! TEST ABS ENGINE Car GM Com 1982 pute & hi r Cod gher e R - CP eade 9001 r TM 6) Plug the Code Scanner into the test connector • The Code Scanner only fits ONE WAY into the test connector. • The Code Scanner will not harm the vehicle computer. Note: The Code Scanner does not use all of the test connector contacts.
• A code 12 is always sent even when the computer sees no problem. This tells you the computer diagnostic checks are working properly. • All codes are two (2) digits long. Example of code 12 only: ❊ PAUSE ❊❊ FLASH (pause) FLASH FLASH (longer pause) ❊ PAUSE ❊❊ 9) Turn Ignition Key OFF FLASH (pause) FLASH FLASH (longer pause) ❊ PAUSE 10)Remove Code Scanner and Reinstall Connector Cover, if supplied The computer system is now back to normal operation.
Erasing ABS Codes from Computer Memory: Bosch 2U (Version C) Erase codes from memory whenever you complete a repair or to see if a problem will occur again. Note: The computer will automatically erase codes after several restarts (typically 100) if the problem does not return. Proceed as follows: 1) Turn the ignition ON switch to the ON position. The antilock lamp should turn OFF after 3 to 4 seconds.
ABS Code Meanings: Bosch 2U (Version C) IMPORTANT: Always follow vehicle service manual procedures for any ABS repairs! (Manual listings on page 4.) 12 Diagnostic System Operational. This code is always sent. 21 Right Front Wheel Speed Sensor circuit. Checks for open, shorted or intermittent condition in subject circuit. Vehicle speed must be equal to or greater than 4 MPH for this code to set. 22 Right Front Toothed Wheel Frequency Error.
51 Right Rear Solenoid Valve circuit. This code will set if the physical position of the subject valve does not match the commanded position as given by the EBCM (Electronic Brake Control Module). 55 (Vehicleswith Traction Control) Left Rear Solenoid Valve circuit. This code will set if the physical position of the subject valve does not match the commanded position as given by the EBTCM (Electronic Brake and Traction Control Module).
SYSTEM 5: Teves Mark II (Version A) 1989 Bonneville, Bonneville SSE, Delta 88, DeVille, Electra, Fleetwood, 98 Regency, Park Avenue 1990 Bonneville, Bonneville SSE, Delta 88, DeVille, Electra, Fleetwood, 98 Regency, Park Avenue Pre-Diagnostic Visual Inspection Functional Check Complete all steps before reading trouble codes! 1) Turn the ignition key to the ON position, but do not start the engine. 1) Check brake fluid level 2) The anti-lock lamp should illuminate for at least 3 seconds.
nication Link (ALCL) or simply test connector. • The connector is located under the dashboard on the driver’s side. –If the anti-lock lamp is ON, and the brake warning lamp is ON, refer to the proper diagnostic chart in the vehicle service manual. –If the anti-lock lamp is OFF, and the brake warning lamp is OFF, then this indicates normal system operation, or an intermittent problem. Intermittent trouble codes may or may not be stored.
11)Turn Ignition Key OFF ❊ ❊❊ Code 23 looks like: ❊❊ PAUSE ❊❊❊ FLASH FLASH (3 second pause) FLASH FLASH FLASH (then light stays on.) Erasing ABS Codes from Computer Memory: Teves Mark II (Version A) 10)Get More Codes (if any) from Flashing “Anti-Lock” Light • Do this step after first code has been flashed and anti-lock light is ON steadily. • Do NOT turn ignition switch off. – Remove Code Scanner from test connector. Then... – Re-install Code Scanner into test connector.
ABS Code Meanings: Teves Mark II (Version A) IMPORTANT: Always follow vehicle service manual procedures for any ABS repairs! (Manual listings on page 4.) 11 EBCM (Electronic Brake Control Module) Failure. In most cases, this code indicates an EBCM failure. Follow the appropriate chart to check the ground circuit. 12 EBCM (Electronic Brake Control Module) Failure. In most cases, this code indicates an EBCM failure. Follow the appropriate chart to check the ground circuit. 21 Main Valve.
51 Left Front Wheel Hydraulic Pressure Reduction fault. This code is the result of an incorrect response to a hydraulic circuit pressure reduction command as sent by the EBCM (Electronic Brake Control Module). Note: This code may also be sent along with Code 71, which has the same meaning. 52 Right Front Wheel Hydraulic Pressure Reduction fault. This code is the result of an incorrect response to a hydraulic circuit pressure reduction command as sent by the EBCM (Electronic Brake Control Module).
SYSTEM 6: Teves Mark II (Version B) 1989 Eldorado, Reatta, Riviera, Seville, Toronado 1990 Eldorado, Reatta, Riviera, Seville, Toronado, Trofeo Pre-Diagnostic Visual Inspection position). Both the anti-lock and brake lamps should be ON during cranking. If they are not, refer to the proper diagnostic chart in the vehicle service manual. 4) When the engine starts, allow it to run for 30 seconds, and then turn it OFF for 10 seconds.
Reading ABS Codes: Teves Mark I (Version B) or it may be recessed behind a panel. An opening in the panel allows access to recessed connectors. • The connector may have a slip-on cover labeled “Diagnostic Connector.” Remove cover for testing. Replace cover after testing. Some vehicles require this cover in place for proper operation. IMPORTANT: Perform all steps in PRE-DIAGNOSTIC VISUAL INSPECTION and FUNCTIONAL CHECK before reading ABS codes! O 1) Safety First! • Set the parking brake.
11)Turn Ignition Key OFF ❊ PAUSE ❊❊ This completes the code reading procedure. At this point you can either: • Have your vehicle professionally serviced. Trouble codes indicate problems found by the computer. or, • Repair the vehicle yourself using trouble codes to help pinpoint the problem. IMPORTANT: Always follow vehicle service manual procedures for any ABS repairs! (Manual listings on page 4) Code 23 looks like: ❊❊ PAUSE ❊❊❊ FLASH FLASH (3 second pause) FLASH FLASH FLASH (then light stays on.
ABS Code Meanings: Teves Mark II (Version B) IMPORTANT: Always follow vehicle service manual procedures for any ABS repairs! (Manual listings on page 4.) 11 EBCM (Electronic Brake Control Module) Failure. In most cases, this code indicates an EBCM failure. Follow the appropriate chart to check the ground circuit. 12 EBCM (Electronic Brake Control Module) Failure. In most cases, this code indicates an EBCM failure. Follow the appropriate chart to check the ground circuit. 21 Main Valve.
48 Any three Wheel Speed Sensor Signals Missing. There are missing signals in three (3) of the four (4) wheel speed sensor circuits. 51 Left Front Wheel Hydraulic Pressure Reduction fault. This code is the result of an incorrect response to a hydraulic circuit pressure reduction command as sent by the EBCM (Electronic Brake Control Module). Note: This code may also be sent along with Code 71, which has the same meaning. 52 Right Front Wheel Hydraulic Pressure Reduction fault.
SYSTEM 7: Kelsey-Hayes RWAL (Rear Wheel Anti-Lock) 1990 1991 1992 1993 1994 Blazer, C & K Series Pickup Truck, Sierra Astro, Blazer, C & K Series Pickup Truck, Jimmy, S Series (2 WD) Pickup Truck, Safari, Sierra Astro, Blazer, C & K Series Pickup Truck, G Series (RWD) Van, Jimmy, R & V Series Truck, S & T Series Pickup Truck, Safari, Sierra, Suburban Astro, Blazer, C & K Series Pickup Truck, G Series (RWD) Van, Jimmy, R & V Series Truck, S & T Series Pickup Truck, Safari, Sierra, Suburban Astro, Blazer, C
Reading ABS Codes: Kelsey-Hayes RWAL IMPORTANT: Perform all steps in DIAGNOSTIC CIRCUIT CHECK before reading ABS codes! • The connector may be in full view, or it may be recessed behind a panel opening. • The connector may have a slip-on cover labeled “Diagnostic Connector.” Remove cover for testing. Replace cover after testing. Some vehicles require this cover in place for proper operation. 2) Verify ABS Problem Currently Exists • Turn the ignition key to the ON position, but do not start the engine.
Code 3 looks like: L O N G vehicle service manual procedures for any ABS repairs! (Manual listings on page 4.) SHORT SHORT ❊ ❊❊ FLASH starts over FLASH FLASH Code 3 NOTE (multiple trouble code storage): This ABS system is only capable of displaying one code at a time. Repair the failure which generated the displayed trouble code, and then repeat the READING ABS CODES procedure to see if any more codes are stored.
ABS Code Meanings: Kelsey-Hayes RWAL IMPORTANT: Always follow vehicle service manual procedures for any ABS repairs! (Manual listings on page 4.) 1 ECM (Electronic Control Module) Failure. This code indicates an anti-lock brake system control module failure, or a misread code. 2 Open Isolation valve or defective ECM (Electronic Control Module). This code indicates an open circuit in the isolation valve or associated wiring. The anti-lock brake system control module may also have failed.
SYSTEM 8: Kelsey-Hayes 4WAL (4 Wheel Anti-Lock) 1992 1993 1994 Astro, Safari Astro, Bravada, S & T Series Blazer, Jimmy, Pickup, Safari, Sonoma, Syclone, Typhoon Astro, Bravada, C & K Series Blazer & Pickup, S & T Series Blazer, Jimmy, Pickup, Safari, Sierra, Sonoma, Suburban, Syclone, Typhoon, Yukon Astro, Bravada, C & K Series Blazer & Pickup, G Series Van, S & T Series Blazer, Jimmy, Pickup, Safari, Sierra, Sonoma, Suburban, Syclone, Typhoon, Yukon Astro, Bravada, C & K Series Blazer & Pickup, G Serie
Reading ABS Codes: Kelsey-Hayes 4WAL 4) Verify Ignition Key is OFF O IMPORTANT: Perform all steps in DIAGNOSTIC CIRCUIT CHECK before reading ABS codes! Note (1990, 1991 only): Codes 21, 22, 25, 26, 31, 32, 35, and 36 will disable ABS system, but are not stored in computer memory. They are erased when ignition is turned off. All other codes are stored in memory when they occur. 1) Take Safety Precautions • Set parking brake, block drive wheels.
2) Put the Code Scanner TEST switch in the ABS position. • After all codes are sent, the whole sequence is repeated. This continues until the ignition key is turned OFF (so you can double check your code list). • All codes are two (2) digits long. TEST ABS 3) Plug the Code Scanner into the test connector for 2 seconds. Remove the Code Scanner for 2 seconds. Repeat this procedure 5 more times. Important: A false code 65 may be created if the plug/unplug procedure is only done twice.
ABS Code Meanings: Kelsey-Hayes 4WAL IMPORTANT: Always follow vehicle service manual procedures for any ABS repairs! (Manual listings on page 4.) 12 ABS System functional, 2WD, service brake not applied. This code indicates that the anti-lock brake system as installed on a 2 wheel drive vehicle is functioning normally. As indicated above, this code should appear without the service brakes applied. 13 ABS System functional, 2WD, service brake applied.
29 All Wheel Speed Sensor Voltage Output Signals are erratic. Trouble code 29 is usually caused by an improperly seated 8 way connector at the EHCU (Electro-Hydraulic Control Unit). Check for corrosion or dirty contacts, and that the connector is properly installed in the EHCU. 31 Right Rear Wheel Speed Sensor Circuit resistance is incorrect. This code is indicative of high resistance in this particular wheel speed sensor circuit.
attach a tag to your defective unit clearly indicating the trouble code(s) reported by the defective EHCU. 43, 44, 47, 48, 53, 54, & 68 all at the same time. If all of these codes appear simultaneously, carefully check all power and ground connections at the EHCU (Electro-Hydraulic Control Unit). 44 Right Front Pulse Width Modulation Valve Solenoid, short circuit. Refer to the explanation under trouble code 43. 45 Left Front Isolation Valve Solenoid, open circuit.
BUICK 96 Century Electra Electra Wagon Estate Wagon Le Sabre Le Sabre Wagon Park Avenue Reatta * Regal Regal Grand National Riviera * Roadmaster Skyhawk Skylark Somerset CADILLAC Cimarron CHEVROLET OLDSMOBILE Beretta Camaro Caprice Cavalier Celebrity Chevette Citation Corsica Corvette El Camino Impala Lumina Monte Carlo Achieva Calais Custom Cruiser Cutlass Calais Cutlass Ciera Cutlass Cruiser Cutlass Cruiser Wagon Cutlass Supreme Cutlass Supreme Classic Delta 88 Eighty-Eight Firenza Ninety-Eight Ome
GM ABS Applications CARS VANS MAKE YEAR MODEL MAKE YEAR MODEL Buick 1989-90 1989-90 1989-91 1989-93 1991 Electra Park Avenue Reatta Riviera Roadmaster Chevrolet GM Van 1989-93 Astro 1990-93 G Series Cadillac 1990-92 1989-90 1989-93 1989-90 1989-93 Brougham DeVille Eldorado Fleetwood Seville TRUCKS Chevrolet 1991 Caprice 1990-91 Corvette Oldsmobile 1989-90 1991 1989-90 1989-92 1990-92 Pontiac 1989-90 Bonneville 1989-90 Bonneville SSE 98 Regency Custom Cruiser Delta 88 Toronado Trofeo MA
ONE (1) YEAR LIMITED WARRANTY Actron Manufacturing Company (“Actron”) warrants to the original purchaser that this product will be free from defects in materials and workmanship for a period of one (1) year from the date of original purchase. Any unit that fails within this period will be replaced or repaired at Actron’s discretion without charge. If you need to return product, please follow the instructions below.
