Air compressor for Pac Brake will not shut off?

[WHazelwood]

The other day my exhaust brake stuck on. I was able to get it to release by releasing the pressure on the accumulator tank. It happend twice on the way home. When I shut the truck off at home the compressor continued to run. The only way to get it to shut off was either pull the fuse or the relay.

The main wire to the compressor was so hot the insulation was melting. Any suggestions?

 

[GSchneuer]

Air compressor for Pacbrake will not shut off.

It sounds like a bad pressure switch.



Gary

 

[CDonaldson]

I'd check the pressure switch as well. There have been problems with the pressure switch mounted on the tank (cold, wet, frozen, etc) if it is mounted under the cab. The solution to the inclimate stuff is to re-locate the switch onto the compressor and get it out of the weather related place.



CD

 

[WHazelwood]

The pressure switch is mounted on the compressor already. It sounded like the pressure switch was leaking out the back side when I got everything shut off. I'll take it off and check it out this pm.

Thanks,

 

[Pacbrake]

Pull the air line off your solenoid check and see if it is stick on, also check to see if the ecm is continuosly putting out a signal, the only reason for the compressor to continously run is a leak, a stuck solenoid, or a short in the system. feel freel to call us if you need further trouble shooting help

 

[WHazelwood]

I checked all the connections and they seemed OK. I had a spare relay and replaced that and everything is working like it should. I had pulled the original relay because the compressor was running even with the key off.

Thanks for the suggestions.