Chart B No Compressor Operation

CIRCUIT DESCRIPTION

The compressor clutch is directly controlled by different components under different engine configurations. In the 5.7 Liter Engine configuration, the ECC Head is in direct control of the A/C clutch via the A/C cutout relay. The ECC Head uses data obtained from the ECM via the ALDL line, in addition to inputs such as engine temperature, low side temperature, etc. in deciding whether to turn the compressor on.

NOTES ON TROUBLE TREE

Any of the following conditions can cause a compressor operation problem:

1. Blown A/C fuse.

2. Opens or Shorts to Ground.

3. Faulty Cycling or Low Freon Press. Switch.

4. Faulty A/C Cutout Relay.

5. Faulty Compressor Clutch.

6. Faulty ECC Head or ECM.

7. Low Refrigerant Pressure.

8. High Engine Temperature.

9. Faulty P/S Pressure Switch.