Pinpoint Test M: DTC U0140

Anti-Lock Control

Pinpoint Test M: DTC U0140

Normal Operation

- DTC U0140 (Lost Communication With Body Control Module (GEM))- sets in continuous and on-demand memory in the ABS module if data messages such as ignition state and ambient temperature data are missing for more than 5 seconds. For a complete list of all network messages, refer to Information Bus.

This pinpoint test is intended to diagnose the following:

- Communication network concern

- Body Control Module (BCM)

- ABS Module

PINPOINT TEST M : DTC U0140

M1 VERIFY THE CUSTOMER CONCERN

- Ignition ON.

- Verify that there is an observable symptom present.

Is an observable symptom present?

Yes
GO to M2.

No
The system is operating normally at this time. The DTC may have been set due to high network traffic or an intermittent fault condition.

M2 CHECK THE COMMUNICATION NETWORK

- Connect the scan tool.

- Ignition ON.

- Using a scan tool, carry out the Network Test.

Does the BCM (Body Control Module) pass the Network Test?

Yes
GO to M3.

No
REFER to Information Bus.

M3 RETRIEVE THE RECORDED DTCs FROM THE BCM (Body Control Module) AND ABS MODULE SELF-TESTS

- Enter the following diagnostic mode on the scan tool: Self-Test- BCM (Body Control Module).

- Enter the following diagnostic mode on the scan tool: Self-Test- ABS Module.

- Check for voltage-related DTCs from the self-tests.

Is DTC B1318 or DTC B1317 recorded?

Yes
For the BCM (Body Control Module), REFER to Body Control Systems.

For the ABS module, REFER to DTC Charts. Antilock Brakes / Traction Control Systems

No
GO to M4.

M4 RECHECK THE ABS MODULE DTCs

- Using a scan tool, clear the ABS module DTCs.

- Ignition OFF.

- Ignition ON.

- Wait 10 seconds.

- Enter the following diagnostic mode on the scan tool: Self-Test- ABS Module.

Is DTC U0140 still present?

Yes
GO to M5.

No
The system is operating correctly at this time. The DTC may have been set due to high network traffic or an intermittent fault condition.

M5 CHECK FOR DTC U0140:00 SET IN OTHER MODULES

- Using the scan tool, clear all CMDTCs (Continuous Memory Diagnostic Trouble Codes).

- Ignition OFF.

- Ignition ON.

- Wait 10 seconds.

- Enter the following diagnostic mode on the scan tool: Self-Test- All CMDTCs (Continuous Memory Diagnostic Trouble Codes).

Is DTC U0140:00 or DTC U0140 set in more than one module?

Yes
INSTALL a new BCM (Body Control Module). TEST the system for normal operation. CLEAR the DTCs. REPEAT the ABS module self-test

No
INSTALL a new ABS module. REFER to Anti-Lock Brake System (ABS) Module . TEST the system for normal operation.