120v circuit works but the 12v circuit does not

[ctgsocal]

I am guessing there is a fuse somewhere in the cable from the batteries, but I can not find it. Where should I look?


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[RJsfishin]

I am guessing there is a fuse somewhere in the cable from the batteries, but I can not find it. Where should I look?
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If no fuse at battery, look at the fuse panel at the DC distribution panel
No 12v when plugged in either ??
Is the converter charging the battery when plugged in ?
Maybe the converter quit, and the batterys are dead. Its not like you gave much information.
Oh, the question, where's the fuse,...mayve there ain't one

[RJsfishin]

Navy E-8 wrote:
Just had a similar problem with my travel trailer. Blown 30 amp fuse between the battery and the trailer. Did not see it the first time around.. Replaced it - problem solved.

Yep, problem solved,.....till it happens again.
A 30 amp fuse doesn't blow because it got tired of doing the same job everyday. It most times blows because of a short circuit. But that's not saying there has never been a defective fuse.

Sorry, thread hijacked !

[ctgsocal]

Thanks for the advice. I'm still searching for that 30A fuse. The positive line branches off to several devices. The coach is a Gulfstream Ultra class C, 1995 model.

[wa8yxm]

FIrst there are two ways a RV is wired and one of those has an "A/B" option as well though B is very very very very rare in modern right

1(A/B)
Battery--fuse/breaer--Swtch--Everything else including the converter

2: Converter--Fuse--Battery--Fuse/breaker--Switch--Everything else

The A/B is some (one very old) converter insists you have a battery.

Option 2 is most common with Inverter/Chargers of 1kw or more (IE mine is a 2kw, but I have both 1 and 2 in my RV. Long story, aftermarket inverter).

How to test.

I like to use a TEST LIGHT this looks like an Ice pick with a wire coming out of the clear handle and a light bulb inside. Any Auto Parts place or department. I have several. I even make them up myself as needed.

Start at the battery.. Clip to NEGATIVE tip to Positive bright light good. No light re-seat the lamp in the handle and re-test Still no light test a known good battery (Your car) bright light on car.. Dead battery on RV.

NOTE at any point a DIM light is not good either)

Move clip to any unpainted frame thing IE: a bolt I've used brake lines and such as well. tip to Positive>> Still bright.. move out along the POSITIVE wire. find teh other end of it. Still bright at the other end (I had one case where the WIRE was the problem) move to the other terminal on whatever it is connected to (Fue or breaker normally at this point) still bright.. Keep moving.

Problem exists between Bright and not bright.

[1492]

Moved from Forum Posting Help and Support

[Navy_E-8]

Just had a similar problem with my travel trailer. Blown 30 amp fuse between the battery and the trailer. Did not see it the first time around.. Replaced it - problem solved.

[Ed_Gee]

First thing to check is the house battery disconnect switch turned on?

[donn0128]

Tt or fiver?
What make, model?
Follow the positive cable from battery you will find it.