Well Trouble-Shot 12V issue...help?

[bdgrizzle]

Found this Jayco Owners forum while working through a head scratcher on my 12V system. Glad to find and offer help as I go. Read a bunch of others' posts and haven't found my problem yet.

I run a 2006 Jay Feather 19H. Had my 12V battery go dead on my last trip (boobdocking) and the system wouldn't take/hold a charge via a generator either. Took the newish battery back and it had a failed cell.

New battery in - but now I am blowing the 12V inline fuse on the battery positive lead. Here is what I've done thus far:
1) Checked the battery - giving 12V
2) Connected to shore power - all AC AND 12V systems go
3) Checked all outlets with a multimeter - working at 120V
4) checked all internal fuses - intact
5) Since the 12V system works on AC, I'm assuming the converter still works (false assumption??)
6) Assuming this means I have a wire short between the 12V battery and the converter somewhere...but tracing it back, I can't find anything.

Battery systems are less intuitive to me - so did I miss something above? Suggestions on next steps?

Thanks in advance!

[bdgrizzle]

And just one more piece of trouble-shooting. I connected to shore power, unplugged the converter, put a new fuse inline onto the 12V lead, and it blew.

Has to be a pinched wire or corrosion on the 12V side between the battery and the converter - right? Having trouble finding anything...

[mike837go]

Double-check your polarity to the battery.


For RV's (from household standards):
White wires are ground -12V.
Black wires are HOT +12V.


Cars and trucks use Black for Ground/Negative and red for +12V. It gets real confusing very quickly.

[bdgrizzle]

Thanks Mike - but nope. Green wire with the inline fuse connected to the cutoff and then to the black wire - that's to the positive terminal. White wire to the negative

[KiwiBruce]

First off disconnect from shore power. It should have fuses that should be blowing also if you have a shorted wire.

Second disconnect the battery, then with multimeter check that the positive post is positive, ie the battery has not been reverse charged, as it sounds like a reverse hook up.

[bdgrizzle]

Ya - both of your suspicions were right on for the symptoms. But I double checked - the battery is correctly charged - not reversed. And just for kicks, I reversed the hot and ground wires in case the wiring was done incorrectly and I never noticed. Reversed it, blue a fuse the same way you would expect it to if reversed.

So identical blow with leads wired correctly or reversed. Too strange.

[moallen]

I wouldn't worry much about the color of the wires. There doesn't seem to be any standard these days.

Instead I would use an ohm meter and make sure what I thought was the ground wire showed continuity to the frame. Then I would check what I thought was each hot/positive wire for NO continuity to the frame.

Do all of this with the battery completely disconnected. That should narrow things down for you.

[RoyBraddy]

There should be two fuses on your 12VDC DISTRIBUTION labeled REVERSE POLARITY. There will also be a fuse or circuit breaker very close to the battery terminal (INLINE) . These three fuse locations will blow if you reverse the polarity even for a second.

What I make a habit of doing is read the the battery terminals before connecting to shore power power. They shuld read 12.65-7VDC if the batteries are fully charged.

When i hook up to shore power power this DC VOLTAGE across the battery terminals should jump up to 13.6VDC telling you the converter/charger is working and the path between the 12VDC DISTRIBUTION panel is good.

Another thing you can also check without the shore power ON is turn on your ceiling lights. They should come on if the battery is connect and working.

I assum you have 12VDC battery in tghe circuit and not two 6VDC batteries. If you have 6VDC batteries they have to be in series to give you 12VDC .

I also never go by what the old connections were when hooking up battery cables. I always look for the word 'NEG' or the symbol '-' on the battery case and make sure this is the battery cable that goes directly to frame ground near the battery setup.

Look for the REVERSE POLARITY FUSES on the 12VDC Distributiuon panel. They will be off to them self and should add up wattage size to the 12VDC output of your converter/charger unit. i.e. if you have a 60AMP converter/charger these two fuses should be 30AMPS each (maybe more)...

Post some model numbers of the converter/charger and the power distribution panel and folks can give better answers...

Roy Ken

[ninjahbob]

I hope I can say this so you can understand what I am trying to say. I had a similar problem. I disconnected the old wire from the battery and I ran a new wire from the battery in thru the front door and made a new connection inside. This helped me determine that it was in fact my positive lead that was damaged and shorting out. I then searched it out and repaired the damage. If it is the main wire you can also just replace the bad wire with a new one and be done with it.
good luck

[bdgrizzle]

@moallen - Good idea that I hadn't done. The ground shows continuity and the hot does not (after checking/replacing a weak multimeter battery *AHEM*). And yes, the battery was disconnected.

@RoyBraddy - I'll look for the two reverse polarity fuses tomorrow by better light tomorrow and try to get some pics. Thanks - didn't know to check there. (and yes - I have one 12VDC and not two 6s)

[Sw7000]

I had a similar issue with my 2006 19H. Mine turned out to be the inverter. The inverter would switch on one time and not another. I cannot recall if I blew fuses at the battery or in the fuse panel. My 19H had an iota dls-45 inverter in it. The other issue I have with this inveter is the power source plug wiggling out of the power block while traveling. So when you plug into shore power, only the micro and one outlet have power. I would run a new power line as someone else mentioned to eliminate a break/crimp/bare spot in the wiring.

[bdgrizzle]

Thanks to all for the help on this issue. Followed all the steps mentioned in the thread, and isolated this down to a 12v wire fault somewhere that I simply cannot find. Gave up Saturday afternoon and had to drop it off an my local RV shop for repair. Trying to get out hunting next week, and I'm out of time to keep novicing away at pulling new wire through insanely tight spaces.

I'll post a final verdict as an FYI. Thanks to all who offered insight

[clubhouse]

I know you mentioned its at the repair shop now and out of your hands.

But I'm curious, did you check the converter reverse polarity fuses? You mentioned intentionally connecting the battery backwards as part of your trouble shooting, that should have blown those fuses.

I think you are right and there is a wire fault on the 12v side, but regardless the polarity fuses need to be confirmed good.

[bdgrizzle]

Never got back to closing this thread. Thanks to all who contributed. Worked through everything mentioned and was lost - figured there was a wire short somewhere internal that I couldn't find, or wasn't willing to disassemble things to find. Took it in for repair.

Turns out, there was something damaged or lodged down in the rubberized hot lead fuze holder - it was keeping the 30A fuse from fully seating, thus shorting. That's it. Ugh. $65 for an improved fuse installation and the hour of labor. And if you are ever traveling through Colorado, I have a FANTASTIC and honest RV repair place. Family biz.

Thanks for all the help!

[norty1]

Thank. It's always nice to know what the resolution was.

[DanNJanice]

Originally Posted by bdgrizzle

Never got back to closing this thread. Thanks to all who contributed. Worked through everything mentioned and was lost - figured there was a wire short somewhere internal that I couldn't find, or wasn't willing to disassemble things to find. Took it in for repair.

Turns out, there was something damaged or lodged down in the rubberized hot lead fuze holder - it was keeping the 30A fuse from fully seating, thus shorting. That's it. Ugh. $65 for an improved fuse installation and the hour of labor. And if you are ever traveling through Colorado, I have a FANTASTIC and honest RV repair place. Family biz.

Thanks for all the help!

Please post the name of the RV repair place. Good service shops deserve to be recognized.

[RAMBO1120]

Which wire from unit to battery is the positive and which is the ground

[JFlightRisk]

Originally Posted by RAMBO1120

Which wire from unit to battery is the positive and which is the ground

If the two main wires are black, and white, the black is positive, and the white is negative to the battery.