## Climate Control

#### A/C Pressure Switch Circuit Troubleshooting

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1. Disconnect the A/C pressure switch 4P connector.

1. Turn the ignition switch ON (II).

1. Measure the voltage between the No. 1 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 4.

NO - Repair open in the wire between the A/C diode A, the ECM and the A/C pressure switch.

1. Turn the ignition switch OFF.

1. Check for continuity between the No. 1 and No. 4 terminals of the A/C pressure switch.

A/C PRESSURE SWITCH

Is there continuity?

YES - Go to step 6.

NO - Go to step 10.

1. Reconnect the A/C pressure switch 4P connector.

1. Disconnect the climate control unit connector A (14P).

1. Turn the ignition switch ON (II).

1. Measure the voltage between the No. 4 terminal of climate control unit connector A (14P) and body ground.

CLIMATE CONTROL UNIT CONNECTOR A (14P)

Wire side of female terminals

Is there battery voltage?

YES - Check for loose wires or poor connections at climate control unit connector A (14P) and at the A/C pressure switch 4P connector. If the connections are good, substitute a known-good climate control unit and recheck. If the symptom/indication goes away, replace the original climate control unit.

NO - Repair open in the wire between the climate control unit and the A/C pressure switch.

1. Check for proper A/C system pressure.

   Is the pressure within specifications?

YES - Replace the A/C pressure switch.

NO - Repair the A/C pressure problem.

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