Ac Compressor Clutch

HOW TO DETECT THE AIR CONDITIONER COMPRESSOR CLUTCH FAILURE

Diagnosis of the part is carried out in several stages. As a first step, you need to check if the clutch activates when the air conditioner is switched on. The diagnosis procedure is dependent on the drive belt length.

If your vehicle uses a long belt to drive auxiliary units, adhere to the following instructions:

1. Turn off the ignition.
2. Shift the transmission lever to neutral.
3. Disconnect the connector of the wire harness going to the clutch, and apply voltage of 12V to it. If the component is serviceable, you should hear a peculiar click that indicates its activation.
4. Disconnect the power supply from the connector.
5. Start the engine.
6. Again apply 12V to the wire that is going to the clutch. The sound of the compressor activation  indicates its good working order.

If a short drive belt is installed on the car, the procedure is as follows:

1. Turn off the ignition.
2. Rotate the pulley on which the belt moves by hand. It should rotate freely.
3. Apply 12V voltage to the wire going to the clutch. If the component is serviceable,  a much greater effort will be required to rotate the pulley by hand.

You will need a multimeter for a more comprehensive diagnosis. With its help, you should measure resistance between the component terminals and check for breakage in the component winding. Then check if the power is supplied to the part by measuring the voltage between the corresponding terminals of the power supply wire. Next, measure the clearance between the pulley and the pressure plate. It should be 0.35-0.65 mm on the average.

If in your vehicle the thermal protection device is located outside the coil housing, you should inspect its operability too. For this purpose, disconnect the device from the clutch and measure the voltage at its terminals.