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

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

K1:

K1-K7:

K8-K10:

K10-K12:

K12-K14:

K15-K17:

K17 Continued:

Normal Operation
Under normal operation, when A/C is requested, a message is sent over the bus from the electronic automatic temperature control (EATC) module to the powertrain control module (PCM). The PCM receives input from the A/C cycling switch through circuit 883 (PK/LB). Voltage is provided to the A/C cycling switch through circuit 1040 (RD/BK)/348 (VT).

The PCM provides a ground for the A/C clutch relay coil through circuit 73 (OG/LB). The A/C clutch relay coil receives ignition voltage through circuit 391 (RD/YE). Ignition voltage for the A/C clutch relay switch is provided through circuit 1810 (LG/OG). When the relay is activated, ignition voltage is supplied to the A/C clutch solenoid through circuit 321 (GY/WH). Ground is supplied for the A/C clutch through circuit 57 (BK).

Possible Causes
- Fuse(s)
- An open in circuit 57 (BK), 73 (OG/LB), 321 (GY/WH), 391 (RD/YE), 1040 (RD/BK)/348 (VT), 883 (PK/LB) or 1810 (LG/OG)
- A/C pressure transducer
- PCM
- A/C control relay
- Electronic automatic temperature control (EATC) module
- A/C cycling switch
- A/C compressor clutch field coil
- A/C clutch air gap