U1040 EBTCM Class II Source ID 28

DTC U1040 EBTCM Class II Source ID 28:

DTC U1040 EBTCM Class II Source ID 28 (Part 1 Of 2):

DTC U1040 EBTCM Class II Source ID 28 (Part 2 Of 2):

CIRCUIT DESCRIPTION
The Body Control Module (BCM) receives a state of health message from the Electronic Brake Traction Control Module (EBTCM) through the Class II serial data link.

CONDITIONS FOR SETTING THE DTC
The BCM does not receive a state of health from the EBTCM.

ACTION TAKEN WHEN THE DTC SETS
The BCM stores DTC U1040 in memory.

CONDITIONS FOR CLEARING THE DTC
^ Under all fault conditions the ignition switch must be cycled from the lock or OFF position to the RUN position before this DTC can change status from current to history.
^ DTC U1040 will clear as a current DTC U1040 and will set as a history DTC U1040 when the BCM detects a state of health message from the BCM.
^ A history DTC will clear after 100 consecutive ignition cycles if the condition for the malfunction is no longer present.
^ Using a scan tool.

DIAGNOSTIC AIDS
^ The following conditions may cause an intermittent malfunction to occur:
- An intermittent open or short to ground in circuit 1122 or 1037.
- Poor connections at the BCM, or the EBTCM.
- An intermittent open in the Splice Pack SP205.
^ The Body Control Module (BCM) may store DTC U1040 if certain diagnostics are performed between the EBTCM and the Data Link Connector (DLC).
^ DTC P1626 will set in the Powertrain Control Module (PCM) when the ignition switch is in the RUN position with the BCM disconnected. When BCM diagnostics and repairs are completed, refer to the Engine Controls for additional information on PCM related DTCs. Powertrain Management

TEST DESCRIPTION
Numbers below refer to the step numbers on the diagnostic table.
2. Checks for an open in the SP205.
3. Checks for a short to ground in circuit 1122.
4. Checks for a short to B+ in circuit 1122.
5. Checks for an open in circuit 1122.
11. Determines whether the malfunction is intermittent or the EBTCM is faulty.