Pinpoint Test C: Lost Communication With Another Module
- Refer to Module Communications Network
for schematic and connector information.
Normal Operation and Fault Conditions
The TCCM communicates directly on the HS-CAN2 network with the ATCM, ABS module, and GWM. The TCCM communicates with the PCM and BCM on the HS-CAN1 network via the GWM. The TCCM communicates with the IPC on the HS-CAN3 network via the GWM.
The TCCM sets a DTC for lost communication when it has not received messages from the suspect module for more than 5 seconds with ignition in RUN and battery voltage in range. Other modules that require data from the suspect module may also set a lost communication DTC if the fault is common to both receiving modules.
DTC Fault Trigger Conditions
DTC Description Fault Trigger Condition TCCM U0100:00 Lost Communication With ECM/PCM "A": No Sub Type Information Sets in continuous memory in the TCCM if powertrain data messages received from the PCM over the HS-CAN are missing for longer than 5 seconds with ignition in RUN and battery voltage in range. TCCM U0121:00 Lost Communication With Anti-Lock Brake System (ABS) Control Module "A": No Sub Type Information Sets in continuous memory in the TCCM if ABS module data messages received from the ABS module over the HS-CAN are missing for longer than 5 seconds. TCCM U0138:00 Lost Communication with All Terrain Control Module: No Sub Type Information Sets in continuous memory in the TCCM if data messages received from the Terrain Management module through the GWM are missing for 5 seconds or longer. TCCM U0140:00 Lost Communication With Body Control Module: No Sub Type Information Sets in continuous memory in the TCCM if data messages received from the BCM through the GWM are missing for 5 seconds or longer. ATCM U0140:00 Lost Communication With Body Control Module: No Sub Type Information Sets in continuous memory in the ATCM if data messages received from the ATCM through the ATCM are missing for 5 seconds or longer. Possible Sources
- Communication concern
- Battery voltage concern
- Network fault
- Intermittent network traffic jam
- PCM, TCM, ABS, ATCM, BCM, IPC
- C1 CHECK FOR LOST COMMUNICATION DTC (DIAGNOSTIC TROUBLE CODE) IN OTHER MODULES
- Enter the following diagnostic mode: Retrieve al CMDTC.
Do any other modules on the vehicle also have a Lost Communication DTC with the suspect module?
Yes Refer to: Communications Network . No GO to C2 - C2 REVIEW CM DTC (CONTINUOUS MEMORY DIAGNOSTIC TROUBLE CODE) FOR LOW VOLTAGE DTC (DIAGNOSTIC TROUBLE CODE)
- Review all module CM DTC for low voltage DTC
Do any modules have a low voltage DTC set?
Yes Resolve all vehicle voltage concerns. Refer to: Charging System . No GO to C3 - C3 INSPECT HS-CAN2 (HIGH-SPEED CONTROLLER AREA NETWORK 2) CONNECTORS
- Refer to Module Communications Network for schematic and connector information. DISCONNECT and INSPECT the HS-CAN2 connectors between the TCCM or ATCM and the suspect module
- Repair:
- corrosion (install new connector or terminals - clean module pins)
- damaged or bent pins - install new terminals/pins
- pushed-out pins - install new pins as necessary
- Connect all connectors. Make sure each connector seats and latches correctly.
- Operate the system and verify the concern is still present.
Is the concern still present?
Yes CHECK OASIS for any applicable TSB. If a TSB exists for this concern, DISCONTINUE this test and FOLLOW TSB instructions. If no TSB address this concern, INSTALL a new suspect module. For U0100, Refer to PCM GUIDED ROUTINE TESTING
Refer to: Electronic Engine Controls . For U0121,
Refer to: Anti-Lock Brake System (ABS) and Stability Control . For U0138,
For U0140,
Refer to: Body Control Module (BCM) .No The system is operating correctly at this time. The concern may have been caused by module connections. ADDRESS the root cause of any connector or pin issues.