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A/C Signal: Testing and Inspection

A/C Circuit:





TIP: IF the air conditioning compressor's magnetic clutch is not activated when the air conditioning is turned ON during idling, it is probable that the cause is a malfunction of the A/C control system.

NOTE: For the following test; Disconnect the negative control module connector, turn the ignition ON, and then turn the A/C switch ON.

1. Measure the Voltage between ECU harness terminals 22 and 115 and ground.

Voltage: Should be 6 Volts or more

If any of the previous tests produce unsatisfactory results, the harness will need to be repaired or replaced. Once repairs have been completed, confirm that the repair has corrected the problem.

If the trouble returns, it is possible that there is an intermittent failure of the component or the ECU. Check for looseness at all harness junctions and test for an intermittent failure.