U0101

Anti-Lock Control - Three-Channel

Pinpoint Test L: DTC U0101

Normal Operation

- DTC U0101 (Lost Communication With Transmission Control Module (TCM))- sets in continuous and on-demand memory in the ABS module if data messages received, such as transmission range, from the Transmission Control Module (TCM) 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

- TCM (Transmission Control Module)

- ABS module

PINPOINT TEST L : DTC U0101

L1 VERIFY THE CUSTOMER CONCERN

- Ignition ON.

- Verify that there is an observable symptom present.

Is an observable symptom present?

Yes
GO to L2.

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.

L2 CHECK THE COMMUNICATION NETWORK

- Ignition ON.

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

Does the module pass the Network Test?

Yes
GO to L3.

No
REFER to Information Bus.

L3 RETRIEVE THE RECORDED DTCs FROM THE ABS MODULE SELF-TEST

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

Is DTC B1317 or DTC B1318 recorded?

Yes
For DTC B1317, GO to Pinpoint Test A. Pinpoint Test A: DTC B1317

For DTC B1318, GO to Pinpoint Test B. Pinpoint Test B: DTC B1318
No
GO to L4.

L4 RECHECK THE ABS MODULE DTCs

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

- Wait 10 seconds.

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

Is DTC U0101 still present?

Yes
GO to L5.

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.

L5 CHECK FOR DTC U0101 SET IN OTHER MODULES

- Using a 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 U0101:00 or DTC U0101 set in more than one module?

Yes
INSTALL a new TCM (Transmission Control Module) (diesel engine) or PCM (gasoline engines). REPEAT the self-test.

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