U1152 CCP Loss of ACM Serial Data Communication - HVAC

CIRCUIT DESCRIPTION

DTC U1152 will set if the ignition is ON and the CCP has lost data communication with the heater and A/C programmer.

Diagnosis of this DTC is dependent upon other system symptoms (DTCs) being present with U1152.

TEST CONDITION(S)

1. Ignition is ON.

FAILURE CONDITION(S)

1. Open circuit.

Action Taken

1. Set DTC U1152.

TROUBLESHOOTING HINTS

1. Using a scan tool, attempt to establish communications with heater and A/C programmer.
2. Check circuit 1807 for an open or short to power or ground.
3. Check that heater and A/C programmer is connected to power and ground.
4. Heater and A/C programmer DTC U1153, loss of CCP serial data communications, may be present with this DTC. If so, this indicates that both the CCP and heater and A/C programmer were functional when the DTC was set, but they could not communicate with one another.
5. If there are multiple Class 2 DTCs current check for a short to ground or voltage in CKT 1807. Refer to Computer System Diagnosis. Testing and Inspection