Test A: Isolation Test

1. Remove the A/C Cut-Out Relay and check the voltage at the following terminals of the harness connector using a test lamp.

Test A Isolation Test:

^ If both checks are good, proceed to step 4.

2. If test lamp does not light on terminal 2, check circuits 495 and 639. Idle Speed Power Steering Pressure Switch (if equipped) should be closed.

^ If switch is open, replace it.

3. Jumper the Pressure Switch connectors.

^ If test lamp now lights at terminal 1 of A/C Cut-Out Relay, check refrigerant charge. If refrigerant charge is normal, replace the Suspect Switch.
^ If test lamp does not light, check circuit 67 for an open. If circuit 67 is good, reconnect A/C Cut-Out Relay and proceed to A/C Compressor Relay Test.

4. With the A/C Cut-Out Relay removed, connect a fused jumper between terminals 1 and 4 of the harness connector.

Test A Isolation Test:

5. Start engine. Connect a test lamp between terminals 2 and 5 of the A/C Cut-Out Relay harness connector.

Test A Isolation Test: