Carrier Comfort Pro Apu

These Carrier APU’s are garbage. Mine has worked properly for about three weeks in the past year. Glad I can idle my company truck.

 

I have a Dynasys so might be a little different but, at the batteries should be another fuse where the power wire for APU is. Really shouldn't need a volt meter to check that, just open the holder and see if the fuse is fried.

 

If that fuse is blown the APU wouldn't even start, that's where it gets it's power from it doesn't have its own battery.

 

Now that you said that I remember one on a truck i drove doing that, haven't had a APU in year's only run a generator now and will never go back.

 

On a side note, you need to pull every single fuse in the box(es), when searching. I lost every light at the back, except the right turn signal. All my light-related fuses were good. Our tech found a slot marked with three letters I can’t remember, but, that fuse was blown. What the letters meant and why every rear light wasn’t on it, we’ve no idea. He said they’ve gotten in the habit of pulling every fuse, when searching for answers.

Glad you found your answer. I hope this underwhelming ThermoKing APU never gives me issues, even though I know it will.