APU.....How to reset???

1st check if you have a switch on the dash that says normal/standby, make sure it is on nrmal, then check the switch on the unit itself out side, just flip the access door up and it should be in the up position. then if all that is ok, then find your controlbox should be mounted under the bunk by one of the access doors. there will be a push button reset switch on 1 end of it, if it is sticking out, you can push it back in to reset it, then try to fire it up. also beacuse the tripac ties into the trucks cooling system there should be some shutoff vlves in the coolant lines running to the apu itself make sure they are on. this is just some quick simple stuff to check if you are not familiar with the tri-pac. hope this helps.

 

This thread tells about the error codes.

 

Had the same code on my old truck after the techs did an inflame. It was a shutoff valve valve on the coolant line. Im sure there are several other reasons for that code but thats my experience.