Compressor wont run

I have power from battery to relay but not from compressor to relay. Relay is good and pressure switch is good. If I run power from battery straight to compressor positive wire the compressor will start. Or if I bridge the power wires on the relay the compressor will start also. I hate electronic problems so anyones help would be great.

Are you SURE the solinoid is good?...

Make sure it is grounded properly.. and make sure your switch wires on the solinoid are hooked up properly also..

If it still don't work.. replace it..

check the ground.... had the same problem!

I'll re-check it. But, I know that when I put a test light to the positive wire from the compressor I have no signal. Shouldnt that always have power ?

Originally posted by LayinSparks



pressure switch is good.

if I bridge the power wires on the relay the compressor will start also

did you try bridging the switch side of the relay where the pressure switch is hooked up to? If you bridge that and the compressor runs, you either have a bad pressure switch or the circuit where the pressure switch is in has a break in it.

Originally posted by LayinSparks



I'll re-check it. But, I know that when I put a test light to the positive wire from the compressor I have no signal. Shouldnt that always have power ? No. Think about it for a second. If it always had power, your compressor would always run.

It sounds like your relay is the issue here, but you can do this to be sure: the pin where your battery connects to the pin where the pressure switch connects. If the compressor turns on, your PS is bad. If it doesn't turn on, your ground could be loose on the relay, or the relay is bad.

You've already stated that bridging the battery and compressor makes it turn on, so the compressor isn't bad, and the wire isn't cut anywhere.