Comfort Master APU: Check oil switch?

if oil level is OK It maybe some other reason it will give you same code .I have the same unit. You could down load the owner manuel on line I did it.

 

I don't know anything about this, which of course has never stopped a truckdriver in the past , but is there some kind of a reset switch or process to do when you change oil?

 

my experience has only been with ThermoKings, but they have a reset button on the side of the black box that they usually locate in the sleeper side box above where the unit is mounted. Any time a fault shuts the unit down, the reset button must be pushed to get it to start again.

The ThermoKing also has a shut off toggle switch under the units cover, so that a mechanic when working on it, doesn't have to worry about it starting up. If it is left in the off position, or bumped off, the unit won't start, much like what you are saying. But again that's on ThermoKings.

 

If it says check the oil switch, it probably has an oil pressure switch as a safeguard. Look for a sensor on the block. It either works on a 5V reference signal (2 wire) or a ground signal (1 wire) back to the units ECM. It could even be a bad oil pump, but I would focus on the switch first. You could check it with a digital volt/ohm meter. I've even seen oil pressure switches get trash in them making them inoperable.
Just because it's fairly new doesn't mean you can't get a faulty part. Is it still under warranty?

Let me go do some research on your unit and I'll be back.

 

Not having much luck. Comfort Master went out of business and their website is suspended. But it looks like you can get parts and service at independent shops.

 

have you found the problem with your comfort master yet? i have the exact same problem. i have swapped out pdms, cabin controllers, oil switches, alternators (tach reading comes from alternator), and now i am checking every inch of wiring to see if there is a break in something. i have also changed software versions and that hasent helped. let me know what you find. i will also let you know if i find anything. thanks

 

If it shuts of immediately, it is the electric fuel pump. It is a Mr. Gasket fuel pump. You can purchase these at most auto parts stores. If it starts and runs for about 30 seconds before it shuts off, the oil is too thick. Summer time run no heavier than 20/5 wgt. winter time run no more than 10/5 wgt. Jusy cause it says Check Oil Switch, you will find out it has nothing to do with the oil switch. If that doesn't work,about the only place left that can help you and get parts is Tim's Mobile Repair in Colton, Ca. Talk to Bruce or Tim. Most of the time if you tell them what the problem is he can tell you the solution. Yes I have one of these pieces of crap.

 

turns out the alternator was still the problem. the replacement i got wasnt self exciting so the tach signal wasnt being sent out. i have another on order and that should fix my problem. thanks jigsaw