2023 23bhe 12v does not work off batteries only

[Jomani]

If you have jumper cables, try jumping straight from the negative battery terminal to the ground bolt you cleaned up. I don’t know where your 7 way connector from the truck is grounded, but you could also jump to that point since you say everything works when connected to the truck. It sounds like your shunt may have gone bad - creating a temporary ground path should bypass it without disconnecting it (troubleshooting only).

[howson]

I pulled a panel and found the solar shunt. But that is where is ended. I can’t figure out how to get to it. any ideas?

For clarification, the Furrion Battery Monitor's shunt is not typically referenced as a "solar shunt"--it's simply a shunt--as the entire rig's 12vDC return path should pass through it to the battery bank.

The rear wall of the passthru is typically held in place by six to eight black screws. It's a thin panel of luan with a felt cover. The water management panel will come off, too, but there might not be much room to pull it out if the plumbing doesn't have any slack. There's also the hazard of inducing a leak, so proceed cautiously if the panel is disturbed.

If you want to know more (too much?) about the Furrion Battery Monitor, check out this thread: https://gdrvowners.com/rallies-aa/11...onitor-seminar

Howard

[Deveasey]

For clarification, the Furrion Battery Monitor's shunt is not typically referenced as a "solar shunt"--it's simply a shunt--as the entire rig's 12vDC return path should pass through it to the battery bank.

The rear wall of the passthru is typically held in place by six to eight black screws. It's a thin panel of luan with a felt cover. The water management panel will come off, too, but there might not be much room to pull it out if the plumbing doesn't have any slack. There's also the hazard of inducing a leak, so proceed cautiously if the panel is disturbed.

If you want to know more (too much?) about the Furrion Battery Monitor, check out this thread: https://gdrvowners.com/rallies-aa/11...onitor-seminar

Howard

How do I test the shunt to see if it is bad before replacing?

[Jomani]

Since the shunt resides between your battery’s negative terminal and all of the ground circuits in your rig, you would first need to get your system working by either bypassing it or removing it (jumper cables are a quick and easy way to bypass it). A shunt is a pretty simple electrical device that has a very low failure rate. It has a very specific resistance so you should see a small voltage drop from one side to the other. A smart shunt is able to measure that voltage drop and accurately determine how much amperage is moving into or out of the battery.

[howson]

Deveasey

Jomani nailed it. Simply bypass the shunt. If the problem is in that area it's much more likely to be a bad crimp than a faulty shunt.

[Jlawles2]

On those nice painted lead terminal adapters, by chance have you looked at the mating side to the terminal? If there is paint on the inside of them this can create issues.

Local parts store and https://www.amazon.com/Schumacher-BA...s%2C129&sr=8-3 or https://www.amazon.com/K-D-Tools-217...s%2C129&sr=8-9 are your best friends with battery terminals. Be careful with the second one as it reams out the inside if not careful.

[Jomani]

I recently reviewed a tester on Amazon that I was leery about at first, but has since become my favorite go to tester for chasing ground issues. Below is a link to that video review. Unlike a standard test light, this connects to both battery terminals and can be used to identity both positive and negative with the probe. The nice thing is that it tones when using it to test grounds. It is also very handy when testing fuses and circuit breakers.

https://www.amazon.com/vdp/01f782497..._DzlJV1Wl0zSlN

[Jlawles2]

BTW Hertz is used to check if something is PWM. With PWM you get a square wave where they vary the on time of the signal as control. In an alternator (for GM) the PWM signal is something liek 128 Hz with a constant voltage of 5.4 VDC. BUT it's a PWM signal so they vary the on time of the voltage to control alternator output.

[Yoda]

I have 12.9v on both bolts here.

Are you positive your battery disconnect switch is on? The red handle need to be pushed and turned so it cant come out. If you can get to the back of it check the power across the terminals.

On my unit a red wire runs to the switch it and a black wire comes back to the power bar and then a black wire to the distribution panel. All 6awg if I remember correctly. Close by were the white negative return wires in a bundle with a blue wire nut and the one wire came from that wire nut to the frame ground. The negative battery cable should run to the shunt and then to frame ground too.. I hope I have that right, as it has been a while since I wired in my 4-6V batterys and Victron battery monitor. The white wire bundle is probably in the junction box to the right in your photo.

Keith

[Deveasey]

As much as I was looking forward to climbing in the pass through storage area to attempt to test the shunt with only 3-4 inches of work room, I decided to look for the negative to the frame. I found two self tapping screws a started pulling screws to get under the belly skirting. Which was such a pain. I found that the head had completely sheered off causing the negative wire to fall off. I drilled a new hole and put in a short lag, cleaned up the rust, put down some black rust oleum and tested the system. I disconnected the negative wires before I re-attached the negative wire.

i found the two self tapping screws in the frame under the “service panel” where the battery monitor was located.

see attached photos.

[Yoda]

As much as I was looking forward to climbing in the pass through storage area to attempt to test the shunt with only 3-4 inches of work room, I decided to look for the negative to the frame. I found two self tapping screws a started pulling screws to get under the belly skirting. Which was such a pain. I found that the head had completely sheered off causing the negative wire to fall off. I drilled a new hole and put in a short lag, cleaned up the rust, put down some black rust oleum and tested the system. I disconnected the negative wires before I re-attached the negative wire.

i found the two self tapping screws in the frame under the “service panel” where the battery monitor was located.

see attached photos.

So is everything working now?

[Jlawles2]

On the broke off head screws where I can get to the back side, I use a set of vise grips (https://www.amazon.com/Tools-VISE-GR...s%2C120&sr=8-1) to lock on to the exposed point and then twist the bolt back out the way it came in. After that I then replace with either a galvanized bolt with lock washer or stainless. I do this to keep from punching extra holes.

[Deveasey]

So is everything working now?

Yes everything is back up and running.

[Deveasey]

My thought is that the bolt was over tightened from factory and after a winter of sub freezing nights the stress broke the head off.