Remove the A/C diode B from the multi-relay box. Check for current flow in both directions between the No. 1 and No. 2 terminals of the A/C diode B. A/C DIODE B Is there current flow in only one direction? YES - Go to step 3. NO - Replace the A/C diode B. Turn the ignition switch ON (II). Measure the voltage between the No. 2 terminal of the A/C diode B 3P socket and body ground. A/C DIODE B 3P SOCKET Is there battery voltage? YES - Go to step 5. NO - Repair open in the wire between the radiator fan relay, fan control relay and the A/C diode B. Turn the ignition switch OFF. Reinstall the A/C diode B.

Disconnect the A/C pressure switch 4P connector. Turn the ignition switch ON (II). Measure the voltage between the No. 3 terminal of the A/C pressure switch 4P connector and body ground. A/C PRESSURE SWITCH 4P CONNECTOR Wire side of female terminals Is there battery voltage? YES - Go to step 10. NO - Repair open in the wire between the A/C diode B and the A/C pressure switch. Turn the ignition switch OFF. Check for continuity between the No. 1 and No. 2 terminals of the A/C pressure switch 4P connector. A/C PRESSURE SWITCH 4P CONNECTOR Wire side of female terminals Is there continuity? YES - Replace the A/C pressure switch. NO - Repair open in the wire between the A/C pressure switch A and B. aaa