Air Conditioning

Compressor Clutch Circuit Troubleshooting (cont'd)

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  1. Connect the No. 1 and No. 2 terminals of the compressor clutch relay 4P socket with a jumper wire.

COMPRESSOR CLUTCH RELAY 4P SOCKET

Does the compressor clutch click ?

YES - Go to step 6.

NO - Go to step 14.

  1. Disconnect the jumper wire.
  2. Turn the ignition switch ON (II).
  3. Measure the voltage between the No. 3 terminal of the compressor clutch relay 4P socket and body ground.

COMPRESSOR CLUTCH RELAY 4P SOCKET

Is there battery voltage?

YES - Go to step 9.

NO - Repair open in the wire between the No. 14 fuse in the under-dash fuse/relay box and the compressor clutch relay.

  1. Turn the ignition switch OFF.
  1. Reinstall the compressor clutch relay.
  2. Make sure the A/C switch is OFF.
  3. Turn the ignition switch ON (II).
  4. Measure the voltage between the No. 18 terminal of ECM/PCM connector E (31P) and body ground with the ECM/PCM connectors connected.

ECM/PCM CONNECTOR E (31P)

Is there battery voltage?

YES - Check for loose wires or poor connections at ECM/PCM connector E (31P). If the connections are good, substitute a known-good ECM/PCM and recheck. If the symptom/indication goes away, replace the original ECM/PCM.

NO - Repair open in the wire between the compressor clutch relay and the ECM/PCM.

  1. Disconnect the jumper wire.
  2. Disconnect the compressor clutch 1P connector.