How to test an AC compressor clutch coil
The AC clutch coil is just several thousand wire windings. When energized with battery voltage, the coil turns into an electro magnet that pulls the AC clutch plate into the pulley which turns the main AC compressor shaft.
What goes wrong with a clutch coil?
The clutch coil can overheat and develop and internal short or the windings may develop an open. The best way to test a clutch coil with with a digital multimeter set to the OHMS scale.
Test AC clutch coil
Disconnect the electrical connector from the clutch coil and touch the two probes to to the 2 terminals in the clutch coil connector. If there’s only one terminal, connect one probe to the terminal and the other probe to a ground location on the compressor.
Coil resistance should be 2-5- Ω. A reading of 0.0-Ω indicates a short in the clutch coil. A reading of 0.L indicates an open in the clutch coil. A reading below 2-Ω or above 5Ω indicates a bad coilPosted on by Rick Muscoplat