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Test J: The Air Conditioning (A/C) Is Inoperative/Does Not Operate Correctly

PINPOINT TEST J: THE AIR CONDITIONING (A/C) IS INOPERATIVE/DOES NOT OPERATE CORRECTLY

Normal Operation
Under normal operation, when A/C is requested, in the dual automatic temperature control (DATC) system, a message is sent over the medium-speed controller area network (MS-CAN) bus to the instrument cluster, then from the instrument cluster through the high-speed controller area network (HS-CAN) bus to the PCM; or in electronic manual temperature control (EMTC) systems, voltage is sent to the instrument cluster through circuit CH434 (GY/YE), then a message is sent from the instrument cluster through the HS-CAN bus to the PCM.

Ignition voltage is provided to the A/C clutch relay switch. When the PCM energizes the relay, ignition voltage is supplied to the A/C clutch through circuit CH401 (VT/WH). Ground is supplied for the A/C clutch through circuit GD120 (BK/GN).

This pinpoint test is intended to diagnose the following:
- Fuse
- Wiring, terminals or connectors
- PCM
- HVAC module - DATC
- HVAC module - EMTC
- A/C evaporator discharge temperature sensor
- A/C pressure transducer
- A/C compressor
- A/C control relay
- Battery junction box (BJB)


J1-J4:






J4-J7:






J7-J9:






J9-J11:






J11-J12:






J12-J14: