Test H: The A/C Does Not Operate/Does Not Operate Correctly

PINPOINT TEST H: THE A/C DOES NOT OPERATE/DOES NOT OPERATE CORRECTLY

H1-H6:

H6-H8:

H8-H10:

H10-H12:

H12 Continued:

H13-H15:

H15-H16:

H16-H17:

H17 Continued:

Normal Operation
Under normal operation, when A/C is requested a signal is sent from the control module to the Smart Junction Box (SJB) through circuit 1397 (GY/WH) (Single-zone EMTC only) or over the SCP BUS (Dual-zone EATC and EMTC only). The SJB sends a message over the SCP bus to the PCM. Voltage is supplied to the A/C cycling switch by circuit 298 (VT/OG) and to the PCM through circuit 347 (BK/YE).

The PCM provides a ground for the A/C clutch relay coil through circuit 331 (PK/YE). 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 931 (OG). When the relay is activated, ignition voltage is supplied to the A/C clutch solenoid through circuit 883 (PK/LB). Ground is supplied for the A/C clutch through circuit 1205 (BK).

Possible Causes
- An open in circuits 1397 (GY/WH), 351 (BN/WH), 439 (TN/LB), 298 (VT/OG), 347 (BK/YE), 391 (RD/YE), 883 (PK/LB) or 331 (PK/YE).
- PCM.
- EATC module.
- EMTC module.
- A/C cycling switch.
- A/C pressure transducer.
- A/C compressor clutch field coil.
- A/C control relay.
- A/C clutch air gap.