U1152 CCP Loss of ACM Serial Data Communication - HVAC

CIRCUIT DESCRIPTION
DTC U1152 will set if the ignition is ON and the Climate Control Panel (CCP) has lost data communication with the Air Conditioning Programmer (ACM).

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

TEST CONDITION(S)
1. Ignition in 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 ACM.
2. Check circuit 1807 for an open or short to power or ground.
3. Check that ACM is connected to power and ground.
4. ACM DTC U1153, loss of Climate Control Panel (CCP) Serial Data Communications, may be present with this DTC. if so, this would indicate that both the Climate Control Panel (CCP) and ACM 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 from a short to ground or voltage in CKT 1807.