APU Tri-pac not charging batteries

The 120a alt part number is 2258. I asked the tech who answered my call about it he said it comes with a wire upgrade kit and it bolts right up but he told me it wasnt necessary to have all that power unless im running crazy electronics and im not.

 

The new batteries are staying charged overnight good enough to not struggle with starting the truck. So I think bad batterie were at least part of the problem for sure. Still haven't had time to get under the tripac. But I'm starting to think maybe that at least one problem was the batteries themselves.

 

Nick what voltage is your inverter showing now with the apu running? Does it change between when apu is off/on..thx

 

It is still only reading around 12.6 to 12.8 with tripac on. And it does drop a little with apu off it does drop a little. So I know the tripac is at least putting out some power.

 

ok thx. im at a TA now and waiting for a bay to open im going to have them test my batteries. One has a leak i believe, want to eliminate that as the culprit. I bought all 4 new at a Petro in October so they are still under warranty from what they are saying. I hope one or more of them are bad and this fixes my problem but we`ll see.

chris

 

I got the cables off the tripac alternator and cleaned them up a little and then put them all back on, started the tripac up and now it is throwing alt code and shutting off. It was not doing this before, so I'm thinking now that it is something in the wiring harness that I maybe wiggled completely loose when I took the wires off the post to brush them off. Anybody have any ideas? I'm thinking I need to probably get this into thermoking and let them fool with it. I'm thinking Since after I went and moved those wires around that it is probably something in the wiring that is bad or corroded and not getting all the power from the alternator to the batteries and therefore throwing the alt code. I do not have the patience to take the whole tripac apart and I know so little about automotive wiring that I am afraid I will short something out. If anyone has any suggestions I am completely open at this point! Thanks you guys who posted in here for all your help!

 

Took truck into ThermoKing in Dubuque this weekend and they diagnosed it as a bad alternator and replaced it. Now it is running at 14.1 volts again and keeping batteries charged with no problem, so after all that racking my brain it ended up being the alternator after all, just like I suspected in the first place. At least I know from now on when I suspect something like that in the first place and I get told that I am basically just imagining things that I need to work my way higher up the food chain before I take "no" for an answer.

 

I had very simular problems to yours, I have had my Tripac for 18 months. I started to have the problems 4 months after install. The apu was installed in Eagan, Mn. by the Company I drive for. The ALT code started to flash, but only when the AC was running. So it didn't code out all the time. I took it to the Thermoking shop in Elkhart, In. and they changed the belt, and told me it was good to go. 2 months later I took it to the same shop with the same problem and they changed the belt again and the artic switch becuse the unit ran all the time even with the AC off. Left there and the unit stopped working all together. took it to the Thermoking shop in Franksville, WI. The ground wire was completely burned through. they fixed it and worked fine for about 2 more months. The ALT code came back on and I stopped in El paso, tx and had the shop look at it there. They replaced the alternator, and the belt again. but they told me that the belt needs to be adjusted about 2 or 3 times in the first week of use. it needs to be tight, you should not be able to feel the vibrations from the belt while it is running, or not very much. I tighted it two times, and ir ran very well for 3 months, then the batteries wouldn't charge correctly, the inverter alarms would go off on high voltage, 15.5 and 16.2. wake me up in the middle of the night and have to start the truck to keep the voltage up for the reefer. I bought a DVM and checked the voltage to the inverter and from the alternator both were showing 15 volts or better. There were no Thermokings near or open, Friday night in Ohio. So Saturday i went down to Napa and got a alternator for a 1993 GMC Yukon, 350, 105 amps the thermoking and the chevy were just about the same size, got the pigtail for the gmc Alternator, and went back to the truck and got the wiring diagram from the web, it seem that both alternators have the same diagrams, spliced the little brown one to the apu, the big red one to the Alternator output, put a new napa belt on and wonderbar. it is running better than ever. I can run the microwave, with out the low voltage lite or alarm for better than 10 mins. The Napa Belt also didn't streach as much. worked out real well for me. I later found the wire from the alternator output on the thermoking alternator was just about worn through, but i could figure out what it was hitting, and the alternator adjustment bolt was broke, so i made a new one out of 3/8 threaded stock and turned the bracket around bottom of the APU so I could adjust it with just taking the front bottom cover down and not the all of the bottom covers.

 

Webstermike1,

Thanks for the head up. Do you recall the NAPA belt #? I would like to have one as a spare...excuse my ignorance, whats a wonderbar?

 

wunderbar is sorta German for wonderful.

But you can also buy a Stanley Wonderbar!