Help! No power to slides, bunk, or thermistats

[Clenge]

2015 Thor Palazzo 36.1

I disconnected the bedroom air conditioner as I was going to replace it. About an hour later, the living AC quit working? I tried to pull in the slides to put it up for the night, and the slides would not retract. I checked all fuses and breakers. I’m getting 12 V to the fuse panel. The inverter seems to be working. The coach is level. The key is in the on position. The chassis batteries and house are completely charged. I tried short power and generator power. Nothing helps. I have the crude wiring diagram from the Thor owners resource page and I’ve traced everything down. I can’t figure it out and I don’t want to call a service tech to come look at it that’s not familiar with Thor coaches.

In the inverter cabinet at the right rear of the coach I am not getting 12 V power to the left side of the ISO relay whatever that is (see pic) I get power to the right of the relay but nothing to the left side of the relay nor the two wires coming off the top and bottom. Could this be the culprit?

Any other suggestions?

Thanks!

[Rvman12]

Did you try contacting Thor?

[Clenge]

Yes. They ran me through the same troubleshooting steps with no luck. I might try and call back to get a different tech.

[lwmcguir]

Originally Posted by Clenge

2015 Thor Palazzo 36.1

I disconnected the bedroom air conditioner as I was going to replace it. About an hour later, the living AC quit working? I tried to pull in the slides to put it up for the night, and the slides would not retract. I checked all fuses and breakers. I’m getting 12 V to the fuse panel. The inverter seems to be working. The coach is level. The key is in the on position. The chassis batteries and house are completely charged. I tried short power and generator power. Nothing helps. I have the crude wiring diagram from the Thor owners resource page and I’ve traced everything down. I can’t figure it out and I don’t want to call a service tech to come look at it that’s not familiar with Thor coaches.

In the inverter cabinet at the right rear of the coach I am not getting 12 V power to the left side of the ISO relay whatever that is (see pic) I get power to the right of the relay but nothing to the left side of the relay nor the two wires coming off the top and bottom. Could this be the culprit?

Any other suggestions?

Thanks!

Retrace what you did with your 12v thermostat wiring that caused the disconnect, fix that by isolating, reset, and that will fix your problem

[craigd853]

Originally Posted by Clenge

2015 Thor Palazzo 36.1

I disconnected the bedroom air conditioner as I was going to replace it. About an hour later, the living AC quit working? I tried to pull in the slides to put it up for the night, and the slides would not retract. I checked all fuses and breakers. I’m getting 12 V to the fuse panel. The inverter seems to be working. The coach is level. The key is in the on position. The chassis batteries and house are completely charged. I tried short power and generator power. Nothing helps. I have the crude wiring diagram from the Thor owners resource page and I’ve traced everything down. I can’t figure it out and I don’t want to call a service tech to come look at it that’s not familiar with Thor coaches.

In the inverter cabinet at the right rear of the coach I am not getting 12 V power to the left side of the ISO relay whatever that is (see pic) I get power to the right of the relay but nothing to the left side of the relay nor the two wires coming off the top and bottom. Could this be the culprit?

Any other suggestions?

Thanks!

Hello and sorry for your troubles. You don't say what year you have or the engine but on my 2013 thor there are two main fuse breakers on the firewall inside the engine bay. These if thrown will cause your exact issue. One is a 30 amp and the other may be a 20amp can not remember exactly but never the less if they have been tripped they will have a lever like arm with a bright color on the arm to let you know they are tripped. I say this because the thermostat and slides operate off of 12 volts. Also, is your salesman switch in the on position? Good luck

[Clenge]

I tried contacting Thor support once again. Still no luck. They asked me for the battery layout, and I sent them a picture of it. The response from a senior tech was that the batteries were wired wrong. I never changed anything and they’ve always worked just fine. Then they tell me to take it to a local dealer service center. I can’t afford to put any more money into this coach. If someone else can maybe assist me besides telling me to call Thor, I would appreciate it. I’ve attached a drawing of how the batteries are laid out. It looks like they’re in series and not parallel but I’m not sure that would make a difference would it?

[Clenge]

2015 Palazzo 36.1 Cummins diesel.

[Clenge]

Originally Posted by craigd853

Hello and sorry for your troubles. You don't say what year you have or the engine but on my 2013 thor there are two main fuse breakers on the firewall inside the engine bay. These if thrown will cause your exact issue. One is a 30 amp and the other may be a 20amp can not remember exactly but never the less if they have been tripped they will have a lever like arm with a bright color on the arm to let you know they are tripped. I say this because the thermostat and slides operate off of 12 volts. Also, is your salesman switch in the on position? Good luck

Where is the salesman switch? Its a 2015 Thor Palazzo 36.1 Diesel pusher.

[craigd853]

Originally Posted by Clenge

Where is the salesman switch? Its a 2015 Thor Palazzo 36.1 Diesel pusher.

Hello, on my coach it's right inside the entry door. On your coach I'm not exactly sure but it's the switch that allows your house batteries to power your coach when not hooked up to shore power. The switch that you turn off when leaving the coach for extended periods of time so that 12 volt sources such as the thermostat do not drain the batteries when not in use.

[howzball]

I've had this exact same electrical issue on my 2015 Palazzo 36.1 and it turned out to be that water had gotten into the back full slide motor and was causing electrical problems. It also affected our antenna booster as well as the slides and AC.
The factory slide motors did not have the black rubber type cover over their backside and it would allow water to seep into them.

Only way I ever figured this out, since the ac was out we had to leave it and go for a hotel stay, came back in a couple days when the rain stopped and everything just worked again. Then the next day it rained and the slide wouldn't move so we pulled the motor and just got lucky to see it was all wet.
Since I swapped out the factory motors for the ones with the rear portion covered we've never had it happen.

BTW: I believe the relay in your first photo is the trombetta switch and it's controlled by the BiRD relay, and that's what determines which side has power... it goes back and forth when your coach is running to keep house or truck batteries charged. No power doesn't mean it's not working. Pushing the emergency start switch in the cab might energize it as well.
When you said the key was on... on mine with the key on the slide won't move. It's a safety.

[Clenge]

Thanks! I found the culprit. I visually looked at all fuses and they looked fine. Had a service tech come out and found that the antenna fuse was no good but couldn't rule that out by looking at it. Go figure. Replaced the fuse and everything worked.

[push toy]

Originally Posted by Clenge

I tried contacting Thor support once again. Still no luck. They asked me for the battery layout, and I sent them a picture of it. The response from a senior tech was that the batteries were wired wrong. I never changed anything and they’ve always worked just fine. Then they tell me to take it to a local dealer service center. I can’t afford to put any more money into this coach. If someone else can maybe assist me besides telling me to call Thor, I would appreciate it. I’ve attached a drawing of how the batteries are laid out. It looks like they’re in series and not parallel but I’m not sure that would make a difference would it?

looking at your pic it is wired wrong for series. the two bottom batteries are wrong. dont know how it could have worked B4

[16ACE27]

Originally Posted by push toy

looking at your pic it is wired wrong for series. the two bottom batteries are wrong. dont know how it could have worked B4

Nope, wired correctly for four 6 volt batteries in a a series-parallel configuration.