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Author Topic: A 12V battery bank question?  (Read 371 times)


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A 12V battery bank question?
« on: April 17, 2017, 07:19:27 AM »
2003 Journey.  12V system.  Trombetta battery connect solenoid is up front, which combines batteries when alternator is running.  Doesn't seem to be working right.  Two connections on the trombetta:  one for house, one for chassis batteries.  And a control wire to combine them via dash switch, which is off.  My understanding is that when the alternator is charging the chassis battery, the trombetta is supposed to close and connect the house and chassis batteries to allow house batteries to charge from the alternator.  Last October, the trombetta failed and I replaced it with another identical one.
Last trip, the house battery discharged while driving.  So I thought the trombetta had failed.  Right now, strange voltage readings that I can't figure out.  We are parked in RV park with external 120V connected (but same readings when shore power is turned off).  At the batteries themselves, chassis is 12.6, house is 13.4.  At the Trombetta terminals, house is 13.4, chassis is 13.4.  I can't reconcile the difference in voltage readings of chassis batteries at the battery and at the trombetta.  All readings with engine off.
Any thoughts? Failed wire connection between Trombetta and House battery?  Is there a fuse?
I had intended to add a dual voltage sense relay to combine the batteries to replace the trombetta that I thought had failed.  But the readings make no sense and until I know whats happening, I'm reluctant to do anything.
2003 Winnebago Journey DL 39WD, Freightliner, Cat 3126E 330HP.  Diesel Pusher.

Ernie n Tara

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Re: A 12V battery bank question?
« Reply #1 on: April 17, 2017, 07:57:04 AM »
Sounds like a failed connection between the trombetta and chassis battery, but 13.4 V at the house battery with 120 Vac off is highly unlikely after more han a few minutes as that would be from an operating converter which,  in turn, must have 120Vac.

Ernie 'n Tara

2011 Winn Journey 34y
2012 Jeep Rubicon - Dozer (orange - kinda)
2006 Jeep Wrangler

John Canfield

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Re: A 12V battery bank question?
« Reply #2 on: April 17, 2017, 08:29:43 AM »
I've locked this thread since it's a duplicate of this one.
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