Cleaning Chassis Battery and Sparked-Not Charging

[Top Sergeant]

I have a 2004 40 MDTS. Just returned from maiden voyage, all went well. I wanted to perform battery maintenance and noticed that the negative cables on the chassis batteries were loose enough that I could move them relatively easily. My rear vansco did not have any lights but the coach ran fine. I read here that grounds are the death of the vansco's as well as other electronics. I also wanted to repair small leaks and such so I continued working on it for a couple of days. In the process the batteries died as I was dumb enough to leave the house batteries at the steps switched on overnight. The chassis batteries also died so back to the battery maintenance. In the process of removing the cables and terminals on the chassis batteries I sparked the wrench on the positive post. I found a blown 20 amp fuse in the fuse box mounted in the battery compartment and replaced it. After charging the batteries overnight she started right up but is not charging. The Xantrex is also not coming on line but it could be due to dead house batteries. Are there any other soft points that I can check before going to the alternator? The battery switch in the battery compartment was turned off when I performed the maintenance. I didn't suspect the alternator since it was not running and chassis batteries were switched off. I drove it to storage and have it hooked to 50 amp shore power to hopefully charged all of the batteries back to their normal levels. I want to hit the road next week if any way possible. Any advice or knowledge for checking would be appreciated.
Thanks in advance

[RVPioneer]

Did the rear VMM power up after charging overnight?

How did you determine the alternator was not charging the chassis batteries?

What voltage was displayed on the Actia/speedometer gauge when the engine was running?

[Top Sergeant]

The VMM did light up, initially my actia Guage showed just under 13 volts but dropped as I test drove it for about an hour until the low volt warning came on. I took it to my shore power location and shut everything down and plugged it in. I want to see if that works properly to charge both the house and chassis batteries before further troubleshooting so that I have all of the symptoms.

[Top Sergeant]

Hi Sir,


I checked the coach today after leaving it plugged in all night. I only had the house battery switched on (at the step) and not the chassis main switch in the battery compartment. It didn't seem to charge the house batteries. Not sure if both are required.
With both battery switches on the rear VMM does not light until the engine is running, then rear VMM lights up.

Front VMM's are lit when power is applied. I parked it when the low volt light came on so the engine started normally. 11.9 volts.
Generator clicks as dead battery. Not sure which battery it uses.

Inverter won't come on line. error: low voltage.
Checked all fuses inside coach under bathroom sink: all good

checked all fuses in battery compartment panel: all good

When I sparked the battery cable to ground I blew the 20 Amp yellow fuse on the left side of the fuse panel in the battery compartment and replaced it. All readings taken after replacement.

Checked voltages on all positive poles in fuse panel in battery compartment to include fuses and cables with both battery switches on: 11.9vdc on all.
I took pictures of the VMM's engine on and off as well as both fuse panels, inverter message and dash display. I can't seem to upload from here. Thanks for any assistance


Added the link for the pictures at the top of this message.



Ron McCullough
2004 40MDTS

[Top Sergeant]

Sir,


You will have to right click on the picture icon at the top to see the pictures.
Thanks for any help
Ron McCullough

[RVPioneer]

Ron,

Have you measured the voltage with a meter at the batteries?

11.9v is a 40% state of charge. Nearly dead. Should be 12.6-12.7 after a full charge.

When plugged in, is your Xantrex remote panel showing a charge voltage to the batteries? This should be in the 13.5-14.0 range.

Have you looked for a reset button on the inverter?

The alternator could be bad. It’s also possible that the voltage isn’t getting to the batteries due to a loose connection.

The front VMM being on and the rear being off could be a poor connection in one of the multi pin connectors.

Bob

[Top Sergeant]

Thanks

[Ljwt330]

Originally Posted by RVPioneer

Ron,

Have you measured the voltage with a meter at the batteries?

11.9v is a 40% state of charge. Nearly dead. Should be 12.6-12.7 after a full charge.

When plugged in, is your Xantrex remote panel showing a charge voltage to the batteries? This should be in the 13.5-14.0 range.

Have you looked for a reset button on the inverter?

The alternator could be bad. It’s also possible that the voltage isn’t getting to the batteries due to a loose connection.

The front VMM being on and the rear being off could be a poor connection in one of the multi pin connectors.

Bob

Agree^^.


Batteries, both for house and chassis are not being charged, from either the alternator or shore power.


Alternator should be reading 13-14 volts while in operation. Your last trip shows it was not charging and you were driving off the batteries only, until they were drained. When alternator is charging, chassis batteries are charged first, then when threshold is reached, house batteries receive charge.


When on shore power, the sequence is reversed, with house batteries charging first. Point being, inverter is not charging batteries either. Checking for Reset button may fix that.


Use a meter and check voltage directly at the batteries, both house and chassis. Then, plug in inverter, and recheck. If voltage has not increased to 13+, batteries are not being charged.

[Top Sergeant]

Thanks, you are correct, same 11.9 volts everywhere. I have taken it to a reputable shop for troubleshooting as I don't want to create more issues until I can learn more about the coach.
Thank you for your valuable feedback,
Ron

[RVPioneer]

Do you have the owners manual and schematics for the coach?

[Top Sergeant]

No Sir,
I know that i will probably need to join the Alpine Coach Association along with FMC to become fully engaged. Are they available elsewhere?