My compressor clutch will not engage on a 1997 F150. I am getting +12V at the compressor on one wire, and confirmed a ground connection on the second. We do know that the system is low, we just wanted to make sure the compressor would still work before going trough the work to find the leak and re-charge the system. Any way to check this out, preferably without pulling the compressor out of the truck? It is one of these sort of projects that if the compressor is bad, I will live without AC. Thanks!

 

If you have 12v on one side of the coil and a confirmed ground on the other, you only have two choices:

Either the coil is open (should be around 3-4 ohms) or the clutch gap is too large (should be between 15 and 35 thou ").

Steve

 

When running and select max ac, give the clutch a touch of pressure to reduce the gap. (Towards to engine use a stick or old toothbrush) If the clutch "snaps" in then the clearance is too much. Common on high use trucks of 11 years old. On mine I removed a shim from the center and its been working fine for 40,000 more miles!!