Georgie Boy Maverick Battery Wiring and Solar Lead Question

[rsuther223]

I had to replace both bad batteries. I need some guidance on where the middle black wire goes. I assume that it will connect to the negative terminal. (Stupid mistake since I should have taken a picture of the original connections) This system is connected to solar panels. Both new batteries show 13.5V. If i connect the black wire to the negative terminal, the voltage shows 15volts. Is that typical?

 

[Ex-Calif]

If that is the solar input it makes sense but something is wrong.

There is a heavy cable joining the negative terminals but no heavy negative going to the house.

It would be a guess on my part but it "seems" one of the heavy cables coming through the wall needs to be a negative cable even though both have red tags.

 

[rsuther223]

Thanks. I will make the switch. I dont know why the cable has a red tag?

 

[rsuther223]

Where would the black wire in the middle go?

 

[Ex-Calif]

If possible trace the upper (bulkhead) wire in the photo to ensure it goes to ground first. Big sparks can happen.

If I had to guess I'd say it goes on the upper battery negative post.

But again if there is any doubt get an electrician.

 

[Kirk]

You need to determine which lead is to supply equipment and which goes to the chassis ground, before you do anything else. If you connect them backward you will have a reverse polarity and you may do major damage to things in your RV.

This shows the proper wiring for two 12V batteries connected in parallel to supply an RV, properly. That third wire is probably from the solar system, as Ex-Cal suggested but, you should get out your multimeter and check the voltages and polarity. With the large cables lifted off of the battery, you can measure each one to the chassis and one should show nearly 0 ohms while the other will have a very high reading. The one with 0 ohms should be on the negative battery post, the other on the positive battery post. I suspect that the third wire is from the solar panels as suggested by Ex-Calif, but I would not address that until you know for sure that the batteries are properly connected.

 

[Gary RV_Wizard]

Thanks. I will make the switch. I dont know why the cable has a red tag?

I would not switch anything without first verifying the purpose of each wire. See Kirk's post (#6). That rad tag is prima facie evidence that the cable is intended for a positive post, so do not ignore it until you have credible proof otherwise.

 

[Ex-Calif]

You need to determine which lead is to supply equipment and which goes to the chassis ground, before you do anything else. If you connect them backward you will have a reverse polarity and you may do major damage to things in your RV.
View attachment 2503754
This shows the proper wiring for two 12V batteries connected in parallel to supply an RV, properly. That third wire is probably from the solar system, as Ex-Cal suggested but, you should get out your multimeter and check the voltages and polarity. With the large cables lifted off of the battery, you can measure each one to the chassis and one should show nearly 0 ohms while the other will have a very high reading. The one with 0 ohms should be on the negative battery post, the other on the positive battery post. I suspect that the third wire is from the solar panels as suggested by Ex-Calif, but I would not address that until you know for sure that the batteries are properly connected.

Kirk speaks truth here.

If the battery rack is metal then the battery hold downs with the butterfly nuts should be a good ground.

Check each large cable. One should have continuity (0 ohms) to ground.

The bay above your batteries is the master positive bus. The other cable should have continuity to this bus - likely to the input side of the solenoid.

If both have continuity they are both positive cables.

Note that this is an class C. If there is no engine bank, one of these cables goes to the starter.

Nite it's possible the starter cable will NOT have continuity to the buss.

Is it possible a heavy ground cable fell through below the battery bank and you didn't retrieve it?

 

[rsuther223]

Thank you for all your help. I found the cable reading 0 ohms. I connected this to the negative. I checked the other one with an ohms reading and placed it on the positive. I must find out more about the solar charging. Note: I don't see any other cable that fell down which is a grounding cable.

 

[Ex-Calif]

Sounds like you have it figured.

After my post I realized the chasis/start battery is likely in a different bay so sorry if that confused anything.

 

[rsuther223]

Being a new RV owner, we don't have anything figured out yet. The unit has a 400W solar package from Renogy installed so it is even more confusing. We are over our head. Note: My daughter "gave" this to us about 2 months ago and we are trying to sell it.

 

[Ex-Calif]

You're in the right place to learn.

As for solar and trying not to mansplain too much...

A 12v battery will have a charged static voltage between 12.6 and 13.2 volts.

Consider it like a reservoir. Electricity comes out at 12.6-13.2 volts. To get electricity in you need a higher pressure (voltage) to push electricity in.

So your vehicle alternator will run at about 14.7. Your solar can run at 14.7 or a bit higher, say 15.5v or so.

That's all normal. One leg of the solar goes on positive and one on the opposite battery negative.

You said you had a reading in that range before so the last step is to hook up the two (presumed) solar wires.

 

[Kirk]

The 2006 Georgie Boy Maverick 310 is a 31-foot Class C motorhome built on a Ford V10 gasoline engine chassis. There should be a battery for the chassis somewhere under the hood, in the engine compartment. Typically, they list for around $15,000 to $25,000 depending on mileage and condition. Can you get your daughter to help you figure things out to know if everything is working now? You might be wise to take it to a consignment RV dealer, rather that try to sell something that you know nothing about.

 

[Derby6]

Sounds like you figured it out. In pic, 2 battery negatives are connected together only--never grounded. That center wire is the ground and needs to be connected to the upper left (in picture) negative terminal.

 

[Crik Walker]

I don’t under stand why there are two + leads leaving the battery box. One would be connected to the distribution center + lug but what else needs to be connected the battery bank?

 

[Ex-Calif]

I don’t under stand why there are two + leads leaving the battery box. One would be connected to the distribution center + lug but what else needs to be connected the battery bank?

It likely goes to the engine bay and connects to a paralleling solenoid.

 

[Kirk]

rsuther223​

New Member · From Albany, OR
Joined Aug 29, 2026
Last seen Aug 31, 2026