LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Ford >> 2020 >> Expedition SSV, RWD >> Repair and Diagnosis >> External Pages >> Different variant/trim >> Section 1 (Four-Wheel Drive Systems) >> Diagnosis And Testing >> Four-Wheel Drive Systems - Vehicles With: 1-Speed Torque On Demand Transfer Case >> Pinpoint Tests >> Pinpoint Test G : Lost Communication With Another Module
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Pinpoint Test G : Lost Communication With Another Module

WARNING: This page is about a different variant/trim than selected.
  1. Refer to Module Communications Network for schematic and connector information.

    Normal Operation and Fault Conditions 

    The TCCM expects to receive network data from other modules on HS-CAN2. The TCCM will set a DTC when it has not received messages from a module for more than 5 seconds. Other modules that require data from the suspect module may also set a lost communication DTC.

    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 HS-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 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.

    Possible Sources 

    • Suspect module
    • Battery voltage concern
    • HS-CAN2

  2. G1 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: Communications Network .
    No  GO to  G2
  3. G2 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: Charging System .
    No  GO to  G3
  4. G3 INSPECT HS-CAN2 (HIGH-SPEED CONTROLLER AREA NETWORK 2) CONNECTORS

    • DISCONNECT and INSPECT the HS-CAN2 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 - fully seat pin, install new pins or connector as necessary

    • CONNECT all connectors. Make sure each connector seats and latches correctly.

    • Operate the system and verify if 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 . For U0121, ABS GUIDED ROUTINE For U0140, Refer to BCM Guided Routine .
    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.