No 12 volt DC in coach

[Snowman77]

My 2017 Thor Chateau 28Z has no 12 volt power in the coach. The battery is fully charged. All 12 volt equipment works fine with shore power or generator. But nothing works without shore power or generator. I can’t find any wiring schematics online so I am having trouble tracing the 12 volt wiring once it leaves the coach battery. I don’t believe the converter is the problem since it works fine converting 120 into 12 when on shore or generator power. I’ve tried to contact Thor owner support, but they haven’t ever returned my calls. Ideas please!

[cavie]

Battery disconnect must be "On"or "IN USE". It is at the door.

[Snowman77]

I forgot to mention that I’ve repeatedly flipped the battery disconnect switch Off and on, but still no juice. It sounds like a relay or solenoid is activating when I turn the switch on, but it has no effect.

[cavie]

Originally Posted by Snowman77

I forgot to mention that I’ve repeatedly flipped the battery disconnect switch Off and on, but still no juice. It sounds like a relay or solenoid is activating when I turn the switch on, but it has no effect.

That info is very helpful. It tells me the inline restable fuse at the battery is probably blown. It will be within 6' of the battery. The converter is supplying power when on shore or Gen. Is the battery fully charge. In the seniaro I just described it would not be fully charged. Also find the solenoid and check the power at both sides.

[javelin]

Sounds like your latching relay is "making noise" when you operate the use/store switch. If we "assume" that is working OK then typically there is a 50 amp mini breaker wired in series between the converteroutput/DC fuse panel and the use/store latching relay which then connects converter output to the coach batteries. A lot of folks spend hours looking for the location of the 50 amp mini breaker so they can reset it (tiny little reset button on it typically). This may be your problem.

Some coaches may also have a 100 amp bussman breaker in series with and mounted close to the coach batteries + terminal fed. This may also have tripped open if your coach uses it (typically feeds hydraulic motor for jacks or generator starter motor). Try looking behind the converter area of your coach for the 50 amp mini breaker; some have found them under appliance kick panels. Someone with your coach can chime in and give more details. Attaching a picture of one 50 amp mini breaker mounted behind the converter under the bed in someone's coach (black arrow point to it).....just to give you a view of what it might look like.

[Boerne RV]

The breaker is tripped between the battery and that solenoid you hear clicking. It is about 6-8”, no more than one foot from the positive terminal. Mounted on the wall beside the battery. Left side, right side, way up high behind the battery, on the backside of the wall behind the battery, (there must be a contest at the factory to see who can make it the hardest to get to) outside the left side wall, right side wall. I have even seen one mounted on the inside of the frame rail! But always 6-8” from the battery.
My money is on the breaker. Could be a loose ground, poor terminal connection, anti reverse polarization fuse blown,

[eaglelen]

Breaker is probably under the bathroom vanity, just forward of the bedroom fuse/breaker panel. Top of shelf on left side of vanity can be unscrewed.

[dbenearsr]

Hi I have a Thor A.C.E. 32.1. Have the same problem, can not find a wiring diagram. My issue is steps won't come out. Left and right turn signal camera and backup camera won't work. Can anyone assist with a wiring diagram? Or give advise as to what is wrong?
Thanks,

[javelin]

Originally Posted by dbenearsr

Hi I have a Thor A.C.E. 32.1. Have the same problem, can not find a wiring diagram. My issue is steps won't come out. Left and right turn signal camera and backup camera won't work. Can anyone assist with a wiring diagram? Or give advise as to what is wrong?
Thanks,

Welcome to the forum. Always a good idea to state your year and model coach if not on your personal details or in your posting.

Unless something has changed, getting specific schematics for coaches is almost impossible from Thor (but worth a try). Also, I don’t know which battery control system the newer ACE’s use, probably BIRD or BIM systems. Do you have two battery control switches near the door or just one use/store switch? If two switches make sure the chassis disconnect is “on” (and makes a clunk sound when turning on) for step operation. The steps are normally powered from the chassis (engine) battery.
I assume your radio and its screen work, just not the cameras? Might be an in line fuse behind the radio or in the fuse panel near driver foot area (if Thor still uses that location) for the cameras. Someone with your specific coach may be able to provide more specific assistance.

[cavie]

Originally Posted by dbenearsr

Hi I have a Thor A.C.E. 32.1. Have the same problem, can not find a wiring diagram. My issue is steps won't come out. Left and right turn signal camera and backup camera won't work. Can anyone assist with a wiring diagram? Or give advise as to what is wrong?
Thanks,

Turn signal and camera issue is a blown fuse. Steps can be a blown fuse or a safety lock oyt swoitch. You need a volt meter.

[Snowman77]

Thanks to all for the advice on fixing my problem. I finally got it done, but it was a huge amount of "surgery" on the RV! After finally finding and checking the small reset under the coach near the battery (it was good), and then finding and checking the reset breaker hidden in the wall underneath the bathroom sink and its fuse (both were good). Then, I took out the entire converter from the bedroom wall and used mirrors to see what was behind the wall. I finally found the solenoid and its fuse. The fuse was good, but the solenoid was crap. A Thor factory tech called me and suggested putting in a temporary jumper cable between the solenoid terminals to confirm if that was why I had no DC power. Sure enough, that solved the problem! Then, I ordered a new solenoid from Wal-Mart and installed it this morning, and now all is good in the electrical world! But, I had to cut a huge hole in the wall of the bathroom beside the toilet to get access to the solenoid. It took some serious wood work and experimenting with stains to find a match to install a patch over the hole, but it's all done now. Thor certainly didn't design these beasts expecting anyone to ever replace these kinds of hidden and impossible to get to parts. ;-((

[cavie]

Originally Posted by Snowman77

Thanks to all for the advice on fixing my problem. I finally got it done, but it was a huge amount of "surgery" on the RV! After finally finding and checking the small reset under the coach near the battery (it was good), and then finding and checking the reset breaker hidden in the wall underneath the bathroom sink and its fuse (both were good). Then, I took out the entire converter from the bedroom wall and used mirrors to see what was behind the wall. I finally found the solenoid and its fuse. The fuse was good, but the solenoid was crap. A Thor factory tech called me and suggested putting in a temporary jumper cable between the solenoid terminals to confirm if that was why I had no DC power. Sure enough, that solved the problem! Then, I ordered a new solenoid from Wal-Mart and installed it this morning, and now all is good in the electrical world! But, I had to cut a huge hole in the wall of the bathroom beside the toilet to get access to the solenoid. It took some serious wood work and experimenting with stains to find a match to install a patch over the hole, but it's all done now. Thor certainly didn't design these beasts expecting anyone to ever replace these kinds of hidden and impossible to get to parts. ;-((

Good job. Next time you need to fix a wall just buy a flat A/C vent cover and paint it brown. Place a piece of cardboard behind it if you need to seal off the hole.

[Lin]

Check Ground Cable connections at the Battery. We had the same issue with our Palazzo and after several days of intense troubleshooting we took it to Freightliner and they fixed it an just about 6 hours. Tech told me he has seen several cases where Thor workers would tighten the Zip Tie holding the Ground Cable in the battery compartment to tight. Over time the vibrations and strain on the cable caused it to come loose.