Pinpoint Test D: Lost Communication With Suspect Module
- Refer to Four Wheel Drive Systems
for schematic and connector information.
Normal Operation and Fault Conditions
The TCCM communicates directly with the PCM and ABS on the FD-CAN network. The TCCM communicates with the ATCM module on the HS-CAN2 network via the GWM. The TCCM communicates with the 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 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 BCM through the GWM are missing for 5 seconds or longer. 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 FD-CAN are missing for longer than 5 seconds with ignition in RUN and battery voltage in range. TCCM U0101:00 Lost Communication with TCM: No Sub Type Information Sets in continuous memory in the TCCM if powertrain data messages received from the TCM over the FD-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 FD-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 ATCM 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. TCCM U0155:00 Lost Communication With Instrument Panel Cluster (IPC) Control Module: No Sub Type Information Sets in continuous memory in the TCCM if IPC data messages received from the IPC through the GWM are missing for longer than 5 seconds. Possible Causes
- Suspect module
- Battery voltage concern
- HS-CAN2
- D1 L1 CHECK FOR LOST COMMUNICATION DTC (DIAGNOSTIC TROUBLE CODE) IN OTHER MODULES
- Enter the following diagnostic mode: Run ALL CMDTC.
Do any other modules on the vehicle also have Lost Communication DTC with the suspect module?
Yes REFER to: Ethernet Module Communications Network - System Operation and Component Description . No GO to D2 - D2 REVIEW CMDTC (CONTINUOUS MEMORY DIAGNOSTIC TROUBLE CODE) FOR LOW VOLTAGE DTC (DIAGNOSTIC TROUBLE CODE)
- Review all module CMDTC for low voltage codes.
Do any modules have low voltage DTC set?
Yes Resolve all vehicle voltage concerns. REFER to: Ethernet Module Communications Network - System Operation and Component Description . No GO to D3 - D3 INSPECT FD-CAN (FLEXIBLE DATA RATE CONTROLLER AREA NETWORK) CONNECTORS
- Refer to Four Wheel Drive Systems for schematic and connector information.
- DISCONNECT and INSPECT the FD-CAN connectors between the TCCM and the suspect module.
- Check for the following:
- 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.
Are any DTC s recorded?
Yes CHECK OASIS for any applicable service articles: TSB, GSB, SSM, or FSA. If a service article exists for this concern, DISCONTINUE this test and FOLLOW the service article instructions. If no service articles address this concern, INSTALL a new suspect module. For U0100,
INSTALL a new Powertrain Control Module (PCM). Only available in the on-line service information RVC:
Generate RVC only works in single-step view Generate RVC requires VIN entry REFER to: Powertrain Control Module (PCM)
(303-14 Electronic Engine Controls, Removal and Installation). For U0101, INSTALL a new TCM. For U0121, INSTALL a new ABS. For U0138, INSTALL a new ATCM. For U0140, INSTALL a new BCM. For U0155, INSTALL a new IPC.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.