Air Conditioning

A/C Pressure Switch Circuit Troubleshooting (cont'd)

21-81  

  1. Turn the ignition switch OFF.
  2. Reconnect the A/C thermostat 3P connector.
  3. Make sure the A/C switch is OFF.
  4. Turn the ignition switch ON (II).
  5. Measure the voltage between the No. 2 terminal of the A/C thermostat 3P connector and body ground with the A/C thermostat 3P connector connected.

A/C THERMOSTAT 3P CONNECTOR

Wire side of female terminals

Is there battery voltage?

YES - Go to step 17.

NO - Replace the A/C thermostat.

  1. Turn the ignition switch OFF.
  2. Disconnect the push switch 10P connector.
  3. Turn the ignition switch ON (II).
  4. Measure the voltage between the No. 3 terminal of the push switch 10P connector and body ground.

PUSH SWITCH 10P CONNECTOR

Wire side of female terminals

Is there battery voltage?

YES - Go to step 21.

NO - Repair open in the wire between the A/C thermostat and the push switch.

  1. Turn the ignition switch OFF.
  2. Disconnect the heater fan switch 7P connector.
  3. Check for continuity between the No. 4 terminal of the push switch 10P connector and the No. 3 terminal of the heater fan switch 7P connector.

PUSH SWITCH 10P CONNECTOR

Wire side of female terminals

HEATER FAN SWITCH 7P CONNECTOR

Wire side of female terminals

Is there continuity?

YES - Go to step 24.

NO - Repair open in the wire between the push switch and the heater fan switch.

  1. Check for continuity between the No. 2 terminal of the heater fan switch 7P connector and body ground.

HEATER FAN SWITCH 7P CONNECTOR

Wire side of female terminals

Is there continuity?

YES - Go to step 25.

NO - Check for an open in the wire between the heater fan switch and body ground. If the wire is OK, check for poor ground at G502.