Solved: No 12 Volt Power

[cookie]

A fellow Heartlander is stuck at a wayside in Texas....with a slide partially extended.
There is no 12 volt to the coach after the breakers.
Breaker is reset, battery cut off is on, 13+ volts at the battery no blown fuses at the fuse panel.
Just no 12 volt power anywhere in the coach.
Trying to help over the phone.
Any quick ideas?

Peace
Dave

 

[jimtoo]

Re: No 12 Volt Power

If power at battery and none at breakers, you are talking the little breakers with the red covers near the battery I hope,, then it's got to be battery cable connection or bad disconnect switch if it has one. Does he have volt meter or better yet,, a 12v test light, to just follow the battery cable? Where is their location?

 

[jbeletti]

Re: No 12 Volt Power

Check hots and grounds at all hydraulic solenoids.

What brand Heartland?

Does anything that is hydraulic (other slides, front jacks) work?

 

[cookie]

Re: No 12 Volt Power

I strongly suspect a bad ground somewhere.
We will pursue that a little deeper if I can get him to answer the phone.
They are on US 59 near Victoria.
Update...I just got a call and they managed to plug 120 into the wayside building and got the slide in.
Will trouble shoot more when they arrive at their destination.
Thanks for all the suggestions.

Peace
Dave

 

[happykraut]

Re: No 12 Volt Power

Dave, you said no 12v after the BREAKERS, but 12v doesn't go through breakers. Unless you meant fuses. So if there is 12v before the fuses, but none after, I would look for a bad ground. Ground would be the only thing common to all fuses. Just my 2 cents worth.

 

[danemayer]

Re: No 12 Volt Power

If they got power to the slides when plugged in, it would have come by way of the power converter to the buss-bar. I think maybe the battery power is not getting to the buss-bar circuit breakers.

 

[jbeletti]

Re: No 12 Volt Power

If they got power to the slides when plugged in, it would have come by way of the power converter to the buss-bar. I think maybe the battery power is not getting to the buss-bar circuit breakers.

I agree. I'm leaning towards loose ground or hot cable at the batteries or input to the converter. Happy to hear they got it going. I was burning up Cookie's text message quota with ideas

 

[jnbhobe]

Re: No 12 Volt Power

JB has got it, has to be a ground, You too Bernie but there are curcuit breakers in the system.

 

[JohnDar]

Re: No 12 Volt Power

So, they got 12v when the converter was activated, but not from the battery. Here's a SWAG to go with the rest: battery terminal connectors are corroded and need to be cleaned. Ever have your car not start and cleaning the terminals/connectors was all it took??

 

[happykraut]

Re: No 12 Volt Power

JB has got it, has to be a ground, You too Bernie but there are curcuit breakers in the system.

You're right Jon(wouldn't expect anything different). I was thinking of the breaker panel. Had I thought about it a little more, and I wouldn't have said that, especially when I got two 50A breakers laying on my desk. My dealer sent them to me and I haven't got around to installing them.

 

[wdk450]

Re: No 12 Volt Power

When you say "bad ground", you must mean the battery ground cable, since the converter negative is also tied to ground and the slides worked under converter (AC power supplied to rig). If 13 volts from the battery was on the buss bar, and the slide motor eventually worked, then the slides breaker on the buss bar was not tripped.
One thing that most people don't realize is the modern electronic voltmeters are very high impedance devices, meaning they draw minuscule amounts of current from the circuit under test in taking a voltage reading. This can give you misleading data in the real high current world. It would have been telling to measure the negative battery terminal to chassis ground while engaging the slides switch (drawing 40 amps or so) - ideally, with perfect connections, you would still read 0 volts, but with poor connections you will read appreciable voltage (loss), which is subtracted from the voltage the battery supplies to the slides motor.

 

[convert]

Re: No 12 Volt Power

Thanks for all the suggestions, it appears the problem was aBAD GROUND. Thanks to a good friend and fellow heartlander Dan Halverson. He gave me a hand and found all the wires going to the buss bar behind the battery were loose . the main ground was lose for some time so that it actually discolored the screw. Have had this problem intermitently for about a year. Thanks again to Dan.

Dave you were right all along a bad ground.

Also might add Good Sam Road service would not come out to jump a battery on a 5er. Only will jump on a motor home. just for info.

 

[wdk450]

Re: No 12 Volt Power

Also might add Good Sam Road service would not come out to jump a battery on a 5er. Only will jump on a motor home. just for info.

If you carry jumper cables in your truck (which you might need someday to get your truck started), you could jumper your 5er yourself. I did this once when the trailer battery was down due to a light left on in the back of the trailer while in storage, where I needed to put the slides out to access the light to turn it off. I think I did the truck jumper stuff when I was half way through the job, with a slide stuck out, and the battery finally quit.

 

[Hockster]

Re: No 12 Volt Power

I had a similar problem 2 years ago.
When I was plugged into land power, I had 12V.
When I unplugged, I had nothing.
I found the self taping screw the factory used to ground the ground buss had sheared off.
They had only used 1 screw.
I installed 2 screws, plus I ran a ground wire from the ground buss to the trailer frame as insurance.
I would suggest everyone check their ground buss connection to the coach frame.

Hockster

 

[Bob&Patty]

Re: No 12 Volt Power

Adding a redunant ground in any 12V system is always a good idea. I do this in every car I build. A bad or loose ground connection is the most common cause of electrical problems.

 

[jnbhobe]

Re: No 12 Volt Power

WHAT you have to ground these things???

 

[wdk450]

Re: No 12 Volt Power

WHAT you have to ground these things???

Yes, they (5th wheel RV's) have to be well grounded to keep them from floating away.

 

[Bob&Patty]

Re: No 12 Volt Power

I use a battleship anchor so mine doesnt float away.

 

[StephenKatSea]

Re: No 12 Volt Power

Last year had no 12v when park AC went down. Found the lug on the ground wire running from the batt. at the 12v buss had become loose. Replaced the lug. All was fine. Something you just don't check when running on shore power for lengths of time.