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House battery voltage question

Recently I show a discrepancy in the charge level of my house batteries.
I have 4 6v T145 batteries for the house supply.

Testing each battery I show 6.5v. When checking them together I show about 12.8v on both banks. I checked all batteries at the terminal and the cables. At the isolator I show about 12.8v. This is all with a full charge.

When I plug into shore power or use the generator I show at least 12.8 to 13.2 volts on the Javlina and the Power Watch monitor.

When I run only on the house batteries I show 12.8 on the Power Watch panel and about the same on the batteries when I check directly at the terminal.

The Javlina is a bit more than 1v less and shows about 11.9v

I never used the auto start on the Generator till my last time out. It was the first time I didn't use a shore power connection. I was worried about the discrepancy of the gauges so I set the generator for auto start.

Sure enough when the Javlina display dipped below 11v, and the Power Watch monitor showed 12v. the generator kicked on.

I thought I probably had a bad house battery, I checked them and all tested good.

What would cause the voltage difference between the Javlina gauge and the Power Watch system. The Power Watch and the voltage testing at the batteries seem to check out. I'm also confident in thinking that the auto start would not wait to begin when the batteries had reached below 11v according to the Javlina display.
1995 U320C SE 40'
Jeep 4x4 Commander - Limited - Hemi
"The Pack"  Yogi and Diesel our Airedales -  Charlie our Boxer/Akita mix. Gone but NEVER forgotten Jake our yellow Lab.
NRA Law Enforcement Firearms instructor - Handgun/shotgun
Regional Firearms instructor for national Armored Transp. Co.

Re: House battery voltage question

Reply #1 –
Lon, your coach like mine is getting some age under it's belt. When mine is running the link 1000 shows 13.8-14.2V, the audit shows the same, the dash gauge never shows over 13V. Now turn the Head lights on oil pressure goes down 10psi and the water temp goes up 10 degrees, I have chased the problem for 7 years. I just attribute it to lots of long runs of wire,and connections that are getting old. Checking the charging(both the engine alternator and the inverter charger) system with a meter all is well. Sounds like you may have a connection some where that is loose or dirty. Good luck finding it.
Bruce, Linda, and Macy
Zoey RIP 1/20/19
1999 U295 40' build #5400
2017 silver Jeep Wrangler, 1260 watts of solar on top
Moving around the country

Re: House battery voltage question

Reply #2 –
I added another ground from the alternator to the engine which resolved my gauge problem.
Regards,
Brett

'99 42' Foretravel Xtreme
'14 Brown Motorsports Stacker
'05 Chevy SSR
'02 BMW R1150R

Re: House battery voltage question

Reply #3 –
Check Brett's reply and also clean & tighten the ground bus bar inside the dash.
Peter
Peter & Beth Martin
No Forrest? What have you done?
MC# 15890 until Dec 2016; FMCA #F329677
Cincinnati, OH

Re: House battery voltage question

Reply #4 –
Quote from: Peter & Beth –
Check Brett's reply and also clean & tighten the ground bus bar inside the dash.
Peter

Where under the dash is the ground bar located?
Thanks
1995 U320C SE 40'
Jeep 4x4 Commander - Limited - Hemi
"The Pack"  Yogi and Diesel our Airedales -  Charlie our Boxer/Akita mix. Gone but NEVER forgotten Jake our yellow Lab.
NRA Law Enforcement Firearms instructor - Handgun/shotgun
Regional Firearms instructor for national Armored Transp. Co.

Re: House battery voltage question

Reply #5 –
Quote from: Lon and Cheryl –


Where under the dash is the ground bar located?
Thanks
I may be going to the storage facility today.  If I do, I'll post pictures.
Peter
Peter & Beth Martin
No Forrest? What have you done?
MC# 15890 until Dec 2016; FMCA #F329677
Cincinnati, OH

Re: House battery voltage question

Reply #6 –
This is the ground bar discussed.  The Foretravel uses only green wires for 12VDC circuits as ground.
Peter & Beth Martin
No Forrest? What have you done?
MC# 15890 until Dec 2016; FMCA #F329677
Cincinnati, OH

Re: House battery voltage question

Reply #7 –
I'm jealous, your wires are all nicely bundled together and MUCH neater than the wires I see under my dash.

I don't see the ground bar. I looked behind the dash, under the dash, and in the main wiring compartment in front of the passenger seat.

I will look further, it has to be there someplace.

Thanks for the pictures, at least I know what to be looking for now.
1995 U320C SE 40'
Jeep 4x4 Commander - Limited - Hemi
"The Pack"  Yogi and Diesel our Airedales -  Charlie our Boxer/Akita mix. Gone but NEVER forgotten Jake our yellow Lab.
NRA Law Enforcement Firearms instructor - Handgun/shotgun
Regional Firearms instructor for national Armored Transp. Co.

Re: House battery voltage question

Reply #8 –
Mine is on the wall forward of the dash instruments.
The selected media item is not currently available. Dave Head & Megan Westbrook
Titusville, FL - The Great Outdoors
'98 270 buying this month
Toad is a 2018 F150 XLT

Re: House battery voltage question

Reply #9 –
Quote from: Dave Head –
Mine is on the wall forward of the dash instruments.

Thanks Dave.
I took a look tonight but didn't see it. I felt back behind the upper lip of the dash and looked for the green wires, i think I can feel the grounding studs back there. I will remove the front of the dash gauge assembly this weekend and take a better look.
How much is involved in removing the top of the dash in front of the gauge assembly? If its back there, that would be the most convenient entrance for servicing.
1995 U320C SE 40'
Jeep 4x4 Commander - Limited - Hemi
"The Pack"  Yogi and Diesel our Airedales -  Charlie our Boxer/Akita mix. Gone but NEVER forgotten Jake our yellow Lab.
NRA Law Enforcement Firearms instructor - Handgun/shotgun
Regional Firearms instructor for national Armored Transp. Co.

Re: House battery voltage question

Reply #10 –
Lon on my coach the dash lifts up over the inst panel every thing is right there. The ground bus will be slightely to the left of center, whole bunch of green wires going to it. also one other note there severial grounds from the engine to the frame in the engine bay you might take a look at them as well, along with all of your negitive battery cable connections. I cleaned up all of mine a couple of years ago and check them at every service, that got rid of alot of grimlens.
Bruce, Linda, and Macy
Zoey RIP 1/20/19
1999 U295 40' build #5400
2017 silver Jeep Wrangler, 1260 watts of solar on top
Moving around the country

Re: House battery voltage question

Reply #11 –
Quote from: Lon and Cheryl –

How much is involved in removing the top of the dash in front of the gauge assembly? If its back there, that would be the most convenient entrance for servicing.
It should be hinged toward the windshield.  Snaps closed/open on side toward living area.  Just lift is straight up on that side.  That should give you access to everything under the dash.
1994 U225
build #4514

Re: House battery voltage question

Reply #12 –
Quote from: bbeane –
Lon on my coach the dash lifts up over the inst panel every thing is right there. The ground bus will be slightely to the left of center, whole bunch of green wires going to it. also one other note there severial grounds from the engine to the frame in the engine bay you might take a look at them as well, along with all of your negitive battery cable connections. I cleaned up all of mine a couple of years ago and check them at every service, that got rid of alot of grimlens.

I went out to look again tonight.
 There might be some confusion in describing the lift up dash. I know about lifting and removing the "pod" that covers the area directly behind the gauge panels.

With that removed I still don't see the ground bar. After reading every ones helpful advice I was able to zero in on the approximate area to  search. I reached under the actual dash cover and can feel the ground studs and the braided ground wire, I just can't actually see any of it.

The dash cover I was referring to, and asking about removal, is the cover that extends all the way across the top of the dash. It appears the locators for the dash "pod" are screwed into it. The dash top heat vent also seems to be attached.

Has anybody any advice as to removal of this part of the dash?
Removal of the gauge cluster might offer access to the ground bar too.

My ground bar may be mounted in a different area than others because of the Primus heat system in my coach. There are hot water heat radiators behind the dash for heating of the windshield. Because of this Foretravel may have moved the ground bar further under the dash for clearance of the heat units.
1995 U320C SE 40'
Jeep 4x4 Commander - Limited - Hemi
"The Pack"  Yogi and Diesel our Airedales -  Charlie our Boxer/Akita mix. Gone but NEVER forgotten Jake our yellow Lab.
NRA Law Enforcement Firearms instructor - Handgun/shotgun
Regional Firearms instructor for national Armored Transp. Co.

Re: House battery voltage question

Reply #13 –
I've removed mine completely when working on the wiper assembly. Lots of screws. The vents come out and the piece is also velcro'ed in place. I removed the window trim pieces on each side too to make it easier.
The selected media item is not currently available. Dave Head & Megan Westbrook
Titusville, FL - The Great Outdoors
'98 270 buying this month
Toad is a 2018 F150 XLT

Re: House battery voltage question

Reply #14 –
If you take the dash pad off, you're still going to be looking at plywood all the way across, limiting any more access to the area behind the dash.  Don't you have a mirror on an extension wand and a flashlight?
Regards,
Brett

'99 42' Foretravel Xtreme
'14 Brown Motorsports Stacker
'05 Chevy SSR
'02 BMW R1150R
 

Re: House battery voltage question

Reply #15 –
Quote from: amos.harrison –
If you take the dash pad off, you're still going to be looking at plywood all the way across, limiting any more access to the area behind the dash.  Don't you have a mirror on an extension wand and a flashlight?

I can feel the  bar with my hand. If I reach in I can feel the studs and the braided flat ground wire.
I  think if lower the gauge clusters I will  be able to access the ground bar.
Your mirror idea is a good one. I  will use one to take a look before I start tearing things apart.
1995 U320C SE 40'
Jeep 4x4 Commander - Limited - Hemi
"The Pack"  Yogi and Diesel our Airedales -  Charlie our Boxer/Akita mix. Gone but NEVER forgotten Jake our yellow Lab.
NRA Law Enforcement Firearms instructor - Handgun/shotgun
Regional Firearms instructor for national Armored Transp. Co.