KAL 3840 Automotive Scope / GMM User’s Manual
Menu Overview MENU ( ) COMPONENT TESTS MENU SENSORS ACTUATORS ELECTRICAL IGNITION (or DIESEL) MAIN MENU CHANGE VEHICLE COMPONENT TESTS SCOPE GRAPHING MULTIMETER VEHICLE DATA INSTRUMENT SETUP DANGER W hen ha ndling a ny si gnals higher than 1 50 V peak , don t e lectrica lly a c t i v ate B OTH C H A an d/o r CH B terminal(s) AND USB terminal together a t a tim e . I f they a r e e le c tri ca lly activated simultaneously, a death or a s e ri ous pe rs o na l inj ur y c ou ld be resulted in.
Contents 1. INTRODUCTION Menu Overview 1. Introduction 1.1 Comparing Scan Tools, DSOs and DMMs 1.2 Vehicle Service Manuals 1- 1 1- 2 2. Safety Information Vehicle manufacturers have helped you locate a driveability problem by designing Electronic Control Units with trouble-code generating capabilities. But, the ECUs aren’t perfect because they don’t cover everything (most glitches and intermittents).
If you had a DSO, you could look at the output signal from each of the wheel speed sensors. From this you would have discovered that the left rear wheel speed sensor had some very fast aberrations that caused the ABS computer to act strange. You replace the left rear wheel speed sensor to cure the problem. The scan tools missed this problem because no trouble codes were set and the computer communication bus was too slow to pick up the spikes.
Avoid Fires: • Disconnect the live test lead before disconnecting the common test lead. • Do not position head directly over carburetor or throttle body. Do not pour gasoline down carburetor or throttle body when cranking or running engine. Engine backfire can occur when air cleaner is out of normal position. • Do not perform internal service or adjustment of this instrument unless you are qualified to do so.
3. AUTOMOTIVE ELECTRONIC SIGNALS 3.1 PRIMARY SIGNAL TYPES FOUND IN MODERN VEHICLES Once you become familiar with basic vehicle waveforms it will not matter how new or old the vehicle is, or even who manufactured the vehicle. You will be able to recognize signals that do not look right. Direct Current (DC) Signals The types of sensors or devices in a vehicle that produce DC signals are: • Power Supplies - Battery voltage or sensor reference voltages created by the PCM.
3.2 CRITICAL CHARACTERISTICS OF AUTOMOTIVE ELECTRONIC SIGNALS To minimize this possible interference with the oscilloscope, keep these tips and suggestions in mind: Most interference will be picked up by the oscilloscope test leads. Only 5 critical characteristics (or information types) given from the Automotive electronic signals are important because the vehicle’s PCM considers them important. • Amplitude - The voltage of the electronic signal at a certain point in time.
4. GETTING STARTED 4.1 PRODUCT DESCRIPTION This instrument is a battery-operated 2-channel lab scope, advanced true rms graphing multimeter (GMM) designed expressly for use in the automotive service market. The main purpose of this instrument is to provide advanced troubleshooting capabilities for automotive service technicians in an easy-to-operate format. This instrument offers the following features: • • • • • • • • • • A 25 Mega-sample/Second (one channel minimum) sample rate for rapid data updates.
• GRAPHING MULTIMETER • VEHICLE DATA • INSTRUMENT SETUP 4.2 QUICK TOUR Powering the Instrument The fastest way to set up the instrument to test most automotive devices(sensors, actuators...) and circuits is to choose from one of the built in COMPONENT TESTS. Each test places the instrument in a configuration best suited to display signals for the chosen device or circuit. Press the POWER key to turn the instrument on. The instrument beeps once and turns on.
Next, press the Four Way arrow keys to highlight PIP/SPOUT. Press test the input signal(s). to select. Now, the instrument is ready to • Press the SAVE key to save the present screen in the next memory location. • Press the RECALL key to recall the screen last saved in memory. • Press the CLEAR key to clear all the memory locations. • Press the BACK key to resume measuring or to return to the previous display.
ITEM 4.3 FRONT PANEL CONTROLS KEYS HOLD Key Control Overview to DESCRIPTION Freezes the display (HOLD is displayed at the top right). Also displays a menu to save or recall screens or to clear the memory. These are the Function keys. The function assigned to eac h key is indicated by the Function Key Label displayed above the key on the bottom display. Cursor (Short) key allows you to use cursors for measurements on waveforms.
COM, TRIGGER Used as external trigger for probes with dual banana plugs, such as the RPM Inductive Pickup. 3. Measurement faults or short circuit with the DUAL INPUT SCOPE mode. This occurs when you perform floating measurements with grounding at different points. INPUT A INPUT A TRIGGER (as single input) Used in SCOPE mode to trigger (or start) acquisitions from an external source.
CHANGE VEHICLE Makes you be able to obtain the pin numbers and wire colors for both PCM and the other component connector from HELP ( ) on the selected vehicle you want to test. COMPONENT TESTS Leads to a series of predefined setups to test most common sensors and circuits. SCOPE Use Single Input Scope mode if you want to measure a single signal, INPUT B is turned off. Use Dual Input Scope mode if you want to simultaneously measure two waveforms - one on INPUT A and the other on INPUT B.
Getting Reference Information for the Selected Test Screen Displays Reference information is available at any time by pressing the HELP key. Press when finished viewing each area under the HELP menu. HELP ( ) HELP MENU PIN # / WIRE COLOR TEST PROCEDURE REFERENCE WAVEFORM THEORY OF OPERATION Figure 8. Single and Dual Input scope in COMPONENT TESTS TROUBLESHOOTING TIPS Use Dual Input Scope mode if you want to simultaneously measure two waveforms - one on INPUT A and the other on INPUT B.
KEYS RANGE A MOVE A TRIG LVL SENS LVL The KEYS icon indicates that you can use the Four Way arrow keys to change Volt & Time ranges, to move the waveform position, and to adjust the trigger level for either INPUT A or INPUT B. And also you can use the Four Way arrow keys to adjust the sensitivity level in the COMPONENT TEST (IGNITION mode). Press to toggle among RANGE A , MOVE A , TRIG LVL , and SENS LVL for INPUT A, or among RANGE B , MOVE B , and TRIG LVL for INPUT B.
5. INSTRUMENT OPERATION 4.8 GMM (GRAPHING MULTIMETER) MODE GMM mode plots the results of signal measurements such as frequency as the values change with time. The time range in GMM mode may be set manually from 5 seconds to 24 hours per display. From the MAIN MENU, you can choose 3 independent instrument test modes: Ranges for the vertical scale may also be set manually, and the available range depends upon the measurement being displayed.
Function keys and Result Screen SCOPE displays are defaulted in “Glitch Detection” mode. This means that all signals are sampled at the full sample rate of the instrument and the minimum and maximum excursions are always shown on the display, even if the horizontal time setting is too slow to show each individual sample interval. In this mode, every noise spike of 40 ns and wider will be displayed.
Single-Shot Function AUTO versus NORMAL acquisitions Normally the scope mode automatically repeats the measurements to acquire waveforms by the recurrent acquisition mode. SINGLE-SHOT allows you to perform single acquisition to snap events that occur only once. REPEAT TEST ( ) is used to start a next single acquisition. If you select AUTO, the instrument always performs acquisitions, i.e., it always displays the signals on the input.
Cursor Key Function For VOLTS CURSORS, Volts dif feren ce b etw een C URSO R 1 a nd CURSOR 2 positions on the INPUT A waveform. A cursor is a vertical line or a horizontal line placed over the displayed waveform to measure values at certain points. The instrument can measure signal details by using Cursors. This function is not possible for all tests. Press CURSOR ( ) to display the Function key Menu for cursor operation.
Code Measurement Graphing Type DC VOLT AC VOLT AC+DC VOLT OHM DIODE CONTINUITY RPM FREQUENCY DUTY CYCLE PULSE WIDTH DWELL IGNITION PEAK VOLTS IGNITION BURN VOLTS IGNITION BURN TIME INJECTOR PEAK VOLTS INJECTOR ON TIME TEMPERATURE LIVE DC Average AC Average AC+DC Average Ohms Diode drop Continuity RPM Frequency Duty Cycle Pulse Width Dwell Ignition Peak Volts Ignition Burn Volts Ignition Burn Time Injector Peak Volts Injector On Time Temperature °C, °F Live Continuous Continuous Continuous Continuous Co
Testing Resistance, Diode, and Continuity Testing Frequency, Duty Cycle, or Pulse Width Use this menu option to test resistance, diode forward voltage, and the continuity of wiring and connections. Connect the test lead tip and test lead ground across the object to be tested. MENU ( ) GRAPHING MULTIMETER GMM OHM FREQUENCY CONTINUTY OPEN CLOSE OHM Press to measure resistance. DUTY CYCLE PULSE WIDTH Press to test diodes. Press to test continuity of wiring and connections.
SINGLE cylinder waveform Testing Current Use this menu option to test current with a current probe. (optional accessory) SPARK VOLTAGE GMM AMPERES DC AC AC+DC RANGE 10 mV/A REPEAT TEST Press to measure DC current. BURN VOLTAGE P ress to measure AC true rms current. BURN TIME Press to select between 10 mV/A, and 100 mV/A. Press to measure AC+DC true rms current. Testing Injector Peak Volts and On Time MENU ( ) Don’t forget to set the Current Probe to zero before using it for measurements.
INSTRUMENT SETUP : Use this menu option to set the following: • Optimal settings for display. • Optimal settings for noise filter to each INPUT. • Auto-Power-Off ON and OFF and adjusting Auto-Power-Off Time. • Language for menus and help text. • Scope Calibration DISPLAY OPTIONS MENU USER LAST SETUP: You can change the Power-On display from VEHICLE DATA MENU (default) to the last display having been displayed just before the instrument was turned off.
Normal. Use Normal acquisition mode to acquire 480 points and display them at the SEC/DIV setting. 5.6 FREEZING, SAVING, AND RECALLING SCREENS Hold Mode The HOLD key enables you to freeze the current display. This makes it possible to examine occasional waveform anomalies and to stop the GMM mode at the end of a manual sweep test. The instrument provides eight memory locations to which you can save the current screen along with its setup.
The screen from memory 4 is displayed. OK • Press to remove the message and the following Function Key Labels will be displayed on the screen. MEMORY RECALL BACK SEARCH 4 WFM ERASE RUN • Use and to display the previous or the next screens in memory. These keys are effective only if more than one screen has been saved in memory. The number indicates the recalled memory location. Press to select the displayed screen.
Noise Filter 6. AUTOMOTIVE DIAGNOSTICS & APPLICATIONS Turn on the Filter (INSTRUMENT SETUP menu) for the input channel you are using. This blocks frequencies above 2 kHz and should reduce ignition impulse noises and other noises of the short spike variety. Ground Connections Many sensors output signals are “single ended” meaning that a single output pin delivers the signal with being referred to a ground pin also on the sensor.
• Troubleshooting Tips ABS Sensor-Magnetic If the amplitude is low, look for an excessive air gap between the trigger wheel and the pickup. • Theory of Operation ABS (Anti-lock Brake System) wheel speed sensors generate AC signals with frequency proportional to wheel speed. The amplitude (peak to peak voltage) increases as the wheel speed increases and is greatly affected by air gap between the magnetic tip and the reluctor wheel.
• Reference Waveform • Symptoms [OBD II DTC’s : P0420 ~ P0424, P0430 ~ P0434] Example of good O2 waveform from property operating TBI system at idle. Hash is normal. Avg. O 2 voltage = 526 mV “Moderate Hash” This is normal VEHICLE INFORMATION YEAR : 1995 MAKE : Plymouth MODEL : Acclaim ENGINE : 2.5 L FUELSYS : Throttle Body Fuel Injection PCM_PIN : 41 BkGrn Wire STATUS : KOER (Key On Running) RPM : Idle ENG_TMP : Operating Temperature VACUUM : 20 In.
• Troubleshooting Tips 4. Press the HOLD key to freeze the waveform on the display for closer inspection. When a catalytic converter is totally deteriorated, the catalytic conversion efficiency as well as the oxygen storage capability of the catalytic converter are essentially lost. Therefore, the upstream and downstream O2 sensor signals closely resemble one another on an inactive converter. 5.
• Test Procedure • Symptoms [OBD II DTC’s: P0110 ~ P0114] 1. Backprobe the terminals on the FT sensor with the CH A lead and its ground lead. Poor fuel economy, hard start, high emissions, tip-in hesitation 2. Start the engine and hold the throttle at 2500 RPM until the trace goes across the screen. • Test Procedure 3. Set the time base to 50 sec/div to see the sensor’s entire operating range, from stone cold to operating temperature. 1.
Knock sensors generate a small AC voltage spike when vibration or a knock from detonation occurs. The bigger the Knock or vibration, the bigger the spike. Knock sensors are usually designed to be very sensitive to the Knocking frequencies (in 5 to 15 kHz range) of the engine block. Throttle Position Sensor (TPS) • Theory of Operation A TPS is a variable resistor that tells the PCM the position of the throttle, that is, how far the throttle is open, whether it is opening or closing and how fast.
• Troubleshooting Tips • Reference Waveform Check the manufacturer’s specifications for exact voltage range. Generally, the sensor output should range from just under 1 V at idle to just under 5 V at wide open throttle (WOT). There should be no breaks, spikes to ground or dropouts in the waveform. P - P = 13.7 V FREQ = 89.2 Hz Peak voltage indicates WOT Voltage decrease identifies enleanment (throttle plate closing) Voltage increase identifies enrichment.
• Symptoms [OBD II DTC’s: P0340 ~ P0349, P0365 ~ P0369, P0390 ~ P0394] Long cranking, poor fuel economy, emissions problem Optical CranKshaft Position (CKP) Sensor • Theory of Operation • Test Procedure These CKP sensors are classified as “CKP Sensors - High Resolution” in industry. 1. Connect the CH A lead to the sensor output or HI and its ground lead to the sensor output LO or GND.
• Troubleshooting Tips The duty cycle of the waveform changes only when a “sync” pulse is displayed. Any other changes in duty cycle can mean troubles. • Reference Waveform PK - PK = 9.93 V FREQ = 33.1 Hz The top and bottom corners of the waveform should be sharp. However, the left upper corner may appear rounded on some of the higher frequency (high data rate) optical distributors. This is normal.
• Symptoms [OBD II DTC’s: P0340 ~ P0349, P0365 ~ P0369, P0390 ~ P0394] Long cranking time, poor fuel economy, emissions failure • Test Procedure 1. Connect the CH A lead to the sensor output or HI and its ground lead to the sensor output LO or GND. 2. With KOER (Key On, Engine Running), let the engine idle, or use the throttle to accelerate or decelerate the engine or drive the vehicle as needed to make the driveability, or emissions, problem occur. 3.
• Troubleshooting Tips The duty cycle of the waveform changes only when a “sync” pulse is displayed. Any other changes in duty cycle can mean troubles. • Reference Waveform P - P = 6.93 V FREQ = 131 Hz The top and bottom corners of the waveform should be sharp. However, the left upper corner may appear rounded on some of the higher frequency (high data rate) optical distributors. This is normal.
• Symptoms [OBD II DTC’s: P0500 ~ P0503] Analog Manifold Absolute Pressure (MAP) Sensor Improper transmission shifting, inaccurate speedometer, problems affecting ABS and cruise control • Test Procedure 1. Raise the drive wheels off the ground and place the transmission in drive. 2. Connect the CH A lead to the sensor output or HI and its ground lead to the sensor output LO or GND. • Theory of Operation Almost all domestic and import MAP sensors are analog types in design except Ford’s MAP sensor.
Check the manufacturer’s specifications for exact voltage range versus vacuum levels, and compare them to the readings on the display. Generally the sensor voltage should range about 1.25 V at idle to just under 5 V at WOT and close to 0 V on full deceleration. High vacuum (around 24 In. Hg on full decel) produces low voltage (close to 0 V), and low vacuum (around 3 In. Hg at full load) produces high voltage (close to 5 V).
Vane type MAF sensors, mainly, consist of a variable resistor (potentiometer) that tells the PCM the position of the vane air flow door. As the engine is accelerated and more air passes through the vane air flow sensor, the vane air door is pushed open by the incoming air. The angle of the vane air flow door is proportional to the volume of air passing by it.
• Reference Waveform FREQ = 64.1 Hz MAX = 4.93 V MIN = 0.00 V Frequency increases due to air flow increase from snap accel. Idle air flow here before snap accel. 4. Make sure that the sensor generates the correct frequency for a given RPM or airflow rate. VEHICLE INFORMATIONS YEAR : 1986 MAKE : Oldsmobile MODEL : Toronado ENGINE : 3.8 L FUELSYS : Multiport Fuel Injection PCM_PIN : B6 Yel wire STATUS : KOER (Key On Running) RPM : Snap Acceleration ENG_TMP : Operating Temperature VACUUM : 0-24 In.
• Symptoms [OBD II DTC’s: P0100 ~ P0104] Differential Pressure Feedback EGR (DPFE) Sensor Hesitation, stall, low power, idle problems, excessive fuel consumption, emissions failure • Test Procedure 1. Connect the CH A lead to the sensor output HI and its ground lead to the sensor output LO or GND. 2. With the Key On, Engine Running (KOER), use the throttle to accelerate and decelerate the engine.
• Reference Waveform MAX = 1.86 V MIN = 400 mV Ford EGR Differential Pressure Sensor logged during snap acceleration Engine accelerated here Saturated Switch Type (MFI/PFI/SFI) Injector VEHICLE INFORMATIONS YEAR : 1994 MAKE : Ford MODEL : Explorer ENGINE : 4.0 L FUELSYS : Multiport Fuel Injection PCM_PIN : 27 BrnLtGrn wire STATUS : KOER (Key On Running) RPM : Snap Acceleration ENG_TMP : Operating Temperature VACUUM : 3-24 In.
• Reference Waveform • Test Procedure MAX = 35.3 V MIN = -2.00 V DUR = 3.92 ms PCM turns circuit on here PCM turns circuit off here VEHICLE INFORMATIONS YEAR : 1993 MAKE : Ford MODEL : F150 4WD Pickup ENGINE : 5.0 L FUELSYS : Multiport Fuel Injection PCM_PIN : 58 Tan wire STATUS : KOER (Key On Running) RPM : Idle ENG_TMP : Operating Temperature VACUUM : 19 In. Hg MILEAGE : 66748 1. Connect the CH A lead to the injector control signal from the PCM and its ground lead to the injector GND. 2.
PNP Type Injector • Theory of Operation A PNP type injector driver within the PCM has two positive legs and one negative leg. PNP drivers pulse power to an already grounded injector to turn it on. Almost all other injector drivers (NPN type) are opposite. They pulse ground to an injector that already has voltage applied. This is why the release spike is upside-down. Current flow is in the opposite direction. PNP type drivers can be found on several MFI systems; Jeep 4.
• Reference Waveform Bosch-Type Peak and Hold Injector • Theory of Operation Bosch type Peak and Hold injector drivers (within the PCM) are designed to allow about 4 A to flow through the injector coil, then reduce the flow to a maximum of 1 A by pulsing the circuit on and off at a high frequency. The other type injector drivers reduce the current by using a “switch-in” resistor, but this type drivers reduce the current by pulsing the circuit on and off.
2. Start the engine and hold throttle at 2500 RPM for 2-3 minutes until the engine is fully warmed up and the Feedback Fuel System enters closed loop. (Verify this by viewing the O2 sensor signal.) 3. Shut off A/C and all other accessories. Put vehicle in park or neutral. Adjust lean stop, air bleed, and idle mixture as per recommended service procedures for the carburetor being serviced. 4. Use the Glitch Snare mode the check for signal dropouts.
• Troubleshooting Tips If the waveform has runted (shortened) spike heights, it indicates a shorted EGR vacuum solenoid. If the waveform has a flat line (no signal at all), it indicates a PCM failure, PCM’s EGR conditions not met, or wiring or connector problem. Too much EGR flow can make the vehicle hesitate, loose power, or even stall. Not enough EGR flow can result in emissions with excessive NOx and engine detonation (pinging).
• Reference Waveform • Symptoms VEHICLE INFORMATIONS YEAR : 1993 MAKE : Ford MODEL : Explorer ENGINE : 4.0 L FUELSYS : Multiport Fuel Injection PCM_PIN : 21 Wht-LtBlu wire STATUS : KOER (Key On Running) RPM : Idle ENG_TMP : Operating Temperature VACUUM : 19 In. Hg MILEAGE : 54567 FREQ = 158 Hz MAX = 12.2 V MIN = 6.40 V The idle control output command from the PCM should change when accessories are switched on and off or the transmission is switched in and out of gear.
A door (called the wastegate) is opened and closed to regulate the amount of bypass. The wastegate is controlled by a vacuum servo motor, which can be controlled by a vacuum solenoid valve that receives a control signal from the PCM. When the PCM receives a signal from the MAP sensor indicating that certain boost pressure is reached, the PCM commands the vacuum solenoid valve to open in order to decrease boost pressure. The PCM opens the solenoid valve via a pulse width modulated signal.
Look for the current going through the glow plug to be at its maximum when the ignition key is switched on. Maximum current and operating current specifications may be available from the manufacturer’s service manual. All glow plugs should draw about the same current under cold or hot conditions. 3. Exercise the sensor, device, or circuit while watching for the amplitude of the signal. The amplitude should stay in a predetermined voltage range for a given condition. 4.
2. Make sure power is switched on to the PCM and monitor the voltage level of the V Ref signal from the PCM. Compare it with the manufacturer’s recommended limits. 3. If the voltage level is unstable or the waveform shows spikes to ground, check the wiring harness for shorts or intermittent connections. • Reference Waveform • Test Procedure 1.
• Symptoms Alternator Field/ VR (Voltage Reference) No start, low battery, slow cranking • Theory of Operation • Test Procedure Before performing the alternator output voltage test, the battery’s state of charge should be checked and a battery load test should be performed. 1. Connect the CH A lead to the battery positive post and its ground lead to the battery negative post. 2. Turn off all electrical loads and start the engine. 3.
• Troubleshooting Tips If the voltage is high, there is no command to turn the alternator on or the regulator does not have the ability to decrease the voltage. • Reference Waveform P-P = 373 mV If the voltage is low, the alternator will be on all the time and cause an overcharging state. If the voltage can not be pulled to ground sufficiently, there may be bad regulator within the PCM. Alternator Diode Tested at idle with high beam and wipers on, and A/C blower on high speed.
• Reference Waveform MAX = +473 mV MIN = -509 mV music starts new note here VEHICLE INFORMATIONS YEAR : 1989 MAKE : Buick MODEL : Le Sabre ENGINE : 3.8 L FUELSYS : Multiport Fuel Injection PCM_PIN : CH A to speaker (+) COM to speaker (–) STATUS : KOEO (Key On Engine Off) RPM : 0 ENG_TMP : Ambient Temperature VACUUM : 0 In. Hg MILEAGE : 93640 A few notes from Willie Nelson’s “On The Road Again” Automotive speaker drive signals normally range between 0.5 V and 10 V Peak to Peak.
PIP (Profile Ignition Pickup)/SPOUT (Spark Output) • Reference Waveform • Theory of Operation The most common electronic ignition system found on Ford vehicles (primarily on Ford/Lincoln/Mercury) has been dubbed TFI for Thick Film Ignition. This system uses a Hall Switch in the TFI module, mounted on the distributor, to produce a basic spark timing signal, PIP (Profile Ignition Pickup).
4. locate fouled or damaged spark plugs that cause a cylinder misfire (from the burn line). It’s sometimes advantageous to test the ignition primary when the ignition secondary is not easily accessible. • Symptoms No or hard starts, stalls, misfires, hesitation, poor fuel economy Look for the burn line to be fairly clean without a lot of hash (“noise”). A lot of hash can indicate an ignition misfire in the cylinder due to over-advanced ignition timing, bad injector, fouled spark plug, or other causes.
Firing lines should be equal. A short line indicates low resistance in the wire. A high line indicates high resistance in the wire 1. Connect the capacitive type ignition secondary probe to the CH A input terminal. Firing lines clearly displayed for easy comparison 2.
• Troubleshooting Tips Look for the drop in the waveform where the ignition coil begins charging to stay relatively consistent, which indicates consistent dwell and timing accuracy of individual cylinder. Look for a relatively consistent height on the “arc-over” voltage or firing line. A line that is too high indicates high resistance in the ignition secondary due to an open or bad spark plug wire or a large spark gap.
The secondary POWER/WASTE spark display waveform can be used to test several aspects of EI (or DIS) system operation. This test can be used to : 1. Connect the capacitive type ignition secondary probe to the CH A input terminal. 1. analyze individual cylinder dwell (coil charging time), 2. Connect the CO M input of the test tool to vehicle ground by using a Ground Lead (black) in order to avoid electrical shock before clamping the secondary probe on the coil secondary lead wire. 2.
Some tips to keep in mind : • Always position the piezo pickup on the fuel line at about the same distance from the injector. • Place the pickup on a straight part of the fuel line. Don’t place it on a bent part of the line. • Always compare results with a reference waveform from a good diesel engine to get acquainted with the signal shape. • Always compare signals at the same engine speed (RPM). • Pump timing is critical and should occur within 1 degree of crankshaft rotation. 6.
Diesel Advance 7. Maintenance Diesel pump testers are used to calibrate pumps exactly to the engine’s requirements. The testers monitor the signals from the reference on the engine’s flywheel. The start of the delivery is monitored and timing adjustments can be made at different speeds. We can reveal problems in the timing of the start of fuel delivery compared to the TDC signal of the flywheel sensor through this advance measurement, which cannot be an absolute and accurate diesel pump adjustment test.
8. Specifications General Specifications Operation temperature : 32 ˚F to 104 ˚F (0 ˚C to 40 ˚C) Storage temperature : -4 ˚F to 140 ˚F (-20 ˚C to 60 ˚C) Relative Humidity : 0 % to 80 % at 32 ˚F to 95 ˚F (0 ˚C to 35 ˚C), 0 % to 70 % at 32 ˚F to 131 ˚F (0 ˚C to 55 ˚C) Temperature Coefficient : Nominal 0.1 x (Specified Accuracy) / ˚C (< 18 ˚C or > 28 ˚C ; < 64 ˚F or > 82 ˚F) Max Voltage between any input and Ground : 300 V Max Input Voltage : 300 V GMM Basic DC Accuracy : 0.
Back Probe Pins : 3 ea (red, yellow and black) Trigger 2 mm Adaptor : 3 ea (red, yellow and black) Trigger Source : CH A, CH B, TRIGGER (External trigger) Secondary Pick-up : 1 ea Sensitivity (CH A) : < 1.0 div to 5 MHz Ground Lead for Capacitive Secondary Probe Sensitivity (Trigger) : 0.
(AC+DC) Voltage Measurement Continuity Test Range Resolution DC 500 mV DC 5 V 0.1 mV 0.001 V DC 50 V 0.01 V DC 500 V 0.1 V DC 600 V 1V Accuracy 40 Hz ~ 400 Hz 400 Hz ~ 10 kHz Range 4 cylinder 120 - 20000 RPM 2 cylinder 60 - 10000 RPM Threshold Response time 1.2 V Approx. 70 W 1 ms Open Circuit Voltage 3.0 V Accuracy Diode Test ± (0.8 % + 5 d) ± (3.0 % + 5 d) Range 2.0 V ± (2.
GLOSSARY Terminology Description ABS Antilock Brake System AC Alternating Current AC Coupling A mode of signal transmission that passes the dynamic (AC) signal component to the input (INPUT A or INPUT B), but blocks the DC component. Useful to observe an AC signal that is normally riding on a DC signal, e.g. charging ripple. Acquisition The process of gathering measurement data into the instrument’s memory.
Terminology Description Terminology Description Cursor A vertical or horizontal line (kind of ruler) that you can place on the screen and move horizontally or vertically to measure values at certain points of the waveform. Function Key Labels Labels shown on the bottom display that indicate the function of the function keys to . DC Direct Current Function Key Menu The function key labels listed on the bottom display.
Terminology Description NTC A resistor that has a Negative Temperature Coeffic ient; resistance decreases as temperature increases. O2 Sensor Oxygen sensor Off-time Terminology Description Scan Tool A device that interfaces with and communicates information on a data link. Sample A reading taken from an electrical signal. A waveform is created from a successive number of samples. The part of an electrical signal during which an electrical device is de-energized.
Terminology Voltage Drop Description Voltage lose across a wire, connector, or any other conductor. Voltage drop equals resistance in ohms times current in amperes (ohm’s Law). Wastegate A valve used to limit charge air pressure by allowing exhaust gases to bypass the turbocharger. Waveform The pattern defined by an electrical signal. WOT Wide Open Throttle.
