GM Service Manual Online
For 1990-2009 cars only

Refer to Engine Controls Schematics

ABS/TCC Switch and Transaxle Solenoids


Object Number: 576339  Size: FS
Engine Controls Components
OBD II Symbol Description Notice
Transaxle Sensors and TR Switch
Generator, PCM, Steering Pressure Switch and Oil Level Switch
Handling ESD Sensitive Parts Notice
IGN 1 Relay and SIR, Vent SOL, IGN 1 Fuses
IGN 1 Relay and SIR, Vent SOL, IGN 1 Fuses
Multifunction Lever and Cruise Control Module Power and Ground
Powertrain Control Module (PCM)
.

Circuit Description

Rough roads cause torque on the tires that is transmitted to the powertrain. This slows down the crankshaft giving the appearance of a misfire. The electronic brake and traction control module (EBCM) determines rough road surfaces using input from the wheel speed sensors. The EBCM then sends the rough road data to the PCM via class 2 serial data. The PCM uses the rough road data to enhance the misfire diagnostic. The data allows the PCM to distinguish the crankshaft speed variations caused by rough road surfaces from those caused by true misfires. If the EBCM is unable to identify rough road conditions while the PCM detects a misfire condition, DTC P1380 will set.

Conditions for Running the DTC

    • The engine load is less than 100 percent.
    • The engine speed is less than 6500 RPM.
    • The vehicle speed is more than 1 km/h (0.6 mph).
    • A misfire DTC is occurring and requesting the MIL to be illuminated.

Conditions for Setting the DTC

The PCM detects an EBCM rough road sensing error.

Action Taken When the DTC Sets

    • The PCM will not illuminate the malfunction indicator lamp (MIL).
    • The PCM will store the conditions present when the DTC set as Failure Records data only.

Conditions for Clearing the MIL/DTC

    • The history DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.
    • The DTC can be cleared by using the scan tool Clear DTC Information function.

Diagnostic Aids

DTC P1380 sets because the ABS / TCS system has detected a malfunction which is preventing the EBCM from transmitting correct rough road data to the PCM.

Step

Action

Values

Yes

No

1

Did you perform the Powertrain On-Board Diagnostic (OBD) System Check?

--

Go to Diagnostic System Check - ABS in Antilock Brake System.

Go to Powertrain On Board Diagnostic (OBD) System Check