Workshop Manual

TRANSMISSION CONTROL SYSTEM (4L30–E)
7A1–21
810RT022
PIN 1 – DIAG. SW
PIN 2 – J1850 Bus + L line on 2–wire systems, or
single wire (Class 2)
PIN 3 – Active suspension diagnostic enable
PIN 4 – Chassis ground pin
PIN 5 – Signal ground pin
PIN 6 – (Not used)
PIN 7 – TOD diagnostic enable
PIN 8 – TOD diagnostic enable
PIN 9 – Primary UART
PIN 10 – (Not used)
PIN 11 – (Not used)
PIN 12 – ABS diagnostic or CCM diagnostic enable
PIN 13 – SIR diagnostic enable
PIN 14 – (Not used)
PIN 15 – (Not used)
PIN 16 – Battery power from vehicle unswitched (4
AMP MAX.)
Malfunction Indicator Lamp (MIL)
The Malfunction Indicator Lamp (MIL) looks the same as
the MIL you are already familiar with (“CHECK ENGINE”
lamp). However, OBD II requires for it illuminate under a
strict set of guidelines. Basically, the MIL is turned on
when the PCM detects a DTC that will impact the vehicle’s
emissions.
The MIL is under the control of the Diagnostic Executive.
The MIL will be turned on if a component or system which
has an impact on vehicle emissions indicates a
malfunction or fails to pass an emissions–related
diagnostic test. It will stay on until the system or
component passes the same test, for three consecutive
trips, with no emissions–related faults.
DTC Types
Each DTC is directly related to a diagnostic test. The
Diagnostic Management System sets DTC based on the
failure of the tests during a trip or trips. Certain tests must
fail two (2) consecutive trips before the DTC is set. The
following are the four (4) types of DTCs and the
characteristics of those codes:
B Type A
B Emissions related
B Requests illumination of the MIL of the first trip with a
fail
B Stores a History DTC on the first trip with a fail
B Stores a Freeze Frame (if empty) (DTC Information
for 6VE1 engine)
B Stores a Fail Record
B Updates the Fail Record each time the diagnostic
test fails
B Type B
B Emissions related
B “Armed” after one (1) trip with a fail
B “Disarmed” after one (1) trip with a pass
B Requests illumination of the MIL on the
second
consecutive trip with a fail
B Stores a History DTC on the second consecutive trip
with a fail (The DTC will be armed after the first fail)
B Stores a Freeze Frame on the second consecutive
trip with a fail (if empty) (DTC Information for 6VE1
engine)
B Stores a Fail Record when the first test fails (not
dependent on
consecutive trip fails)
B Updates the Fail Record each time the diagnostic
test fails
(Some special conditions apply to misfire and fuel trim
DTCs)
B Type C (if the vehicle is so equipped)
B Non-Emissions related
B Requests illumination of the Service Lamp or the
service message on the Drive Information Center
(DIC) on the first trip with a fail
B Stores a History DTC on the
first trip with a fail
B Does not store a Freeze Frame
B Stores Fail Record when test fails
B Updates the Fail Record each time the diagnostic
test fails
B Type D
B Non-Emissions related
B Not request illumination of any lamp
B Stores a History DTC on the
first trip with a fail
B Does not store a Freeze Frame
B Stores Fail Record when test fails
B Updates the Fail Record each time the diagnostic
test fails