So I just bought this motorhome. It's a 1979 Dodge Tioga Class C. It's in great shape, but the past owner hooked up the battery wrong it appeared. To where one of the little 2 post circuit breakers would heat up indicating a direct short. I corrected that and still dont have any battery power in the motorhome. The battery rests at about 12.4, so it's not like new but from what I've read it's not considered dead. Could it still have screwed the battery up? The generator keeps it steady at about 12.4ish. I'm thinking the inverter or converter is fried? This is my first motorhome so I have no idea what I'm really looking at. I found the transfer switch I believe, it clicks off when the generator shuts off so I believe that's it. Where would I find the converter or inverter at and how do I know if they're bad? I found a little blue box looking thing that looks similar to a stereo amp under the hood and saw something similar at an rv store in the converter or inverter aisle. Other than that I dont really see anything that looks like what I'm looking for. Thank you guys.

Maybe the ground from the negative battery post is not making ground to where its grounded on the chassis. Corrosion .

12.4 is not dead, but it's about 60 percent discharged. The information that sticks out though is you get 12.4 at the battery when the generator is running. That sounds like you still have a battery shutoff switch or a blown fuse. You are probably going to have to start tracing wires from the house battery to the inside. As bobndot suggested focus on the grounds first. Leave the generator off and the shore power unplugged. Use your meter and measure the voltage between the positive and negative terminals of the battery. This is your battery voltage, write it down somewhere. Every voltage check you take below should show very close to battery voltage.Remove both ends of the ground wire, clean off any rust and reconnect. Check voltage from the battery positive to the frame mounted end of the ground.From there start following the positive wire. Look for any old circuit breakers or fuses. Once you find one use your meter to check the battery voltage on both sides. On a circuit breaker you can connect from each post one at a time to ground. You should get the same battery voltage on each post.If you find a fuse you can poke the positive lead of your meter to the slots on the back of the fuse. You should get the same battery voltage on both sides of the fuse. If you get voltage on one side but not the other, the fuse is blown.Edit: Wait, an RV that old probably has glass fuses. If glass, then measure the voltage from each metal end of the fuse to a good ground.If you can't find a bad fuse or breaker then start looking for the fuse\breaker box. Not sure on a rig that old, but I imagine it's a small panel with a door (probably metal) mounted on the wall somewhere in the living quarters. Find that door and firmly turn every breaker and then back on. Now see if you can find a good enough ground to check both ends of the fuses. I'm assuming they are glass fuses so just measure from each metal end to ground. You should get the same battery voltage reading on all fuses. If you do not get battery voltage, or you see some abnormally low number then you have a switch or blown fuse between the battery and the fuse panel. If you find close to battery voltage at the fuse panel then start the generator and measure the voltage at the fuses again. With the generator running you should be seeing a number higher than battery voltage. If you have higher voltage, then start tracing back toward the battery until you find generator voltage on one side of a fuse or circuit breaker and battery voltage on the other side. Fix or replace any component that shows a difference between the two ends.Good luck and come back and let us know what you find, and we'll have more suggestions.

So I went and got the voltage and it's right at 12.4. Then i tested the 2 circuit breakers/Fuses in the battery box and I'm getting 12.4 on 3/4 posts. So I guess I will start there tomorrow and see if replacing that will change anything. I have a feeling it's a little bit bigger issue than that but maybe I'll get lucky. If that doesnt work, I assume the next step is to follow that line that isn't showing 12.4 and see where it goes, which I'm thinking is the breaker box inside the living quarters and see if theres a fuse popped on that line?

Yes sounds like the plan I would follow. But first look at the breaker with the 0 volts post. Check carefully for a small reset button. Most do not have a button, but some do so it's worth looking. Next you could try disconnecting the wire from the 0 volt post. Give the breaker a minute to cool off and see if you now have 12.4 volts on both posts. If yes then there is a short further downstream tripping the breaker. If no then you have a bad breaker.Another option that might yield some results is to plug in shore power or start the generator. Make sure to reconnect the 0 volt post if you disconnected it previously. If the 0 volt post now has power it tells you the converter/charger and fuses are all good back up to the suspect breaker. But you should be reading something like 13.6 volts on one post and 12.4 on the other post because the breaker is bad and isolating the two posts.

Fuse on converter blows when you reverse polarity.Converter is behind the fuse panel.There are 2 fuses check both that's where i would look unless i misunderstood the post.

Generator/Shore Power Work, Battery Power Doesn't

whemme
Explorer II
Oct 13, 2020
BrocNeal wrote:
whemme wrote:
Be more descriptive, what do you mean by “black tune looking things”? Can’t tell by looking at your photo.

Its the black tube thing at the bottom of the picture. Its hooked to the silver thing in the corner and hooks to the thing on the right side of the picture. Its almost made of like ceramic. The guy told me its a "Ceramic resistor".

My opinion at this point is that the SCR component in this converter has most likely failed due to an earlier reversed polarity house battery hookup. That black ceramic high temperature resistor may also have been damaged. But since the owner is apparently not familiar with basic electronic component terms, his ability to repair this converter is in doubt. The best solution may be just to have the whole system replaced with a new unit by a qualified RV repair shop.
bobndot
Explorer II
Oct 13, 2020
time2roll wrote:
Boondocker $145

Well then in that case,
:B:B:C:C
time2roll
Nomad
Oct 12, 2020
Boondocker $145
bobndot
Explorer II
Oct 12, 2020
time2roll wrote:
It is a resistor. Resistors get larger with higher watt ratings to dissipate the heat.

Either way just replace that converter already.

:B
For a couple of hundred $ you would be getting a multi stage converter .
time2roll
Nomad
Oct 12, 2020
It is a resistor. Resistors get larger with higher watt ratings to dissipate the heat.

Either way just replace that converter already.
BrocNeal
Explorer
Oct 12, 2020
whemme wrote:
Be more descriptive, what do you mean by “black tune looking things”? Can’t tell by looking at your photo.

Its the black tube thing at the bottom of the picture. Its hooked to the silver thing in the corner and hooks to the thing on the right side of the picture. Its almost made of like ceramic. The guy told me its a "Ceramic resistor".
whemme
Explorer II
Oct 12, 2020
Be more descriptive, what do you mean by “black tune looking things”? Can’t tell by looking at your photo.
BrocNeal
Explorer
Oct 10, 2020

I got the converter part out. Where do I go from here? When I got the battery charge board from Progressive, they also sent me some of the black tube looking things because they occasionally go out also, do I try and replace that?
BrocNeal
Explorer
Oct 09, 2020
whemme wrote:
Just wondering if the OP has successfully fixed his charger/convertor problem?

So unfortunately not. I haven't had time lately due to having our first kid, the motorhome has been put on the back burner for a minute. I'm working on getting a new battery for it. So when I took the old battery out, I decided to hook up shore power and see if I got 12 volts on any of the posts I was taking reads off of before. Because I figured if it was converting correctly that I should be able to see at those posts if it is or not. Is that a stupid test? It made sense in my head but don't know if it makes sense or not. But the results were 8 volts on one side and then shore power on the other side. Does that show anything or not? I was working on pulling out the converter since I'm pretty sure thats my issue but haven't gotten around to finishing it since I'm a lot more busy with other things now. Thats what my gut tells me the issue is but this thing has me thinking all sorts of different things so who knows!
whemme
Explorer II
Oct 04, 2020
Just wondering if the OP has successfully fixed his charger/convertor problem?

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