12V question

[nums]

Hi,

My son was messing with my 345 yesterday and something is now messed up in my 12V system. I'd appreciate any trouble-shooting help.

Moho starts great. Generator starts great from control panel. When generator is on, roof AC can on. So, 110V system and motor system are fine.

However, my coach batteries were and continue to be switched off (no change). That said, my steps now won't retract ... even if the generator or motor are running. 12V power loss? Further, the control panel is non-responsive (non-lit) with the exception of using the start/stop button for the generator.

I looked at the fuse panel under my oven and couldn't figure out how to tell if a fuse is blown. Do I seriously have to unbolt these things?

Advice?

Thanks,
terry

[bkahler]

Terry, interesting problem.

I can think of several possibilities but the most likely culprit would be the fuse between the DC fuse panel and the coach batteries. If your setup is like the ones I'm familiar with there should be two large (maybe 3/8" diameter by 1-1/2" long) fuses. Airstream usually installs a fuse on the plus (+) side and also on the negative (-) side so if one of those is blown you will have no power to your DC fuse panel. The fuses would be located near the Univolt and might be hidden by the fuse panel itself.

Typically there is also a selector switch in the battery compartment that allows you to turn off/disconnect the battery feed to the DC panel. However if your DC converter (Univolt) is powered up you should still have DC power at the fuse panel.

I hope this helps.

Brad

[bobmiller1]

The first place I would start is to ask your son what he was doing.....rather than chasing your tail around at a lot of possibilities or advise. Just Saying....Regards, Bob

[nums]

Unfortunately, my 6 year old son pushed every button reachable on the Moho but can't recall anything...

However, I accessed the univolt and saw that it was plugged into a wall socket... so, I tried it on an extension cord and it powers fine and gives me juice to the dc system. Interior lights, etc work... but not powered step...

Couldn't find any inline fuses on 110 system, near coach batteries or near univolt.

[bobmiller1]

Ahh.....now that we know your son's age, you do have a problem.....a good test light might be your best friend !

[mehes]

I'd start at the battery and work my way to the fuse panel. Did your son mess around in the area of the battery? Mine has an isolation switch which looks very impressive to a six year old.


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[nums]

I also went through the fuses in the glove compartment. They all seem intact.

I think the problem may be related to to the step ... he did announce to me that day that he found the automatic step up/down switch (button on door frame near hinges). So, he probably pushed it 500 times. Perhaps related, the step is now not retracting ... either under motor power, generator power or with univolt properly powering other DC wiring (via 110 extension cord).

I'm comfortable using a multi-meter to measure current ... less so chasing unpowered lines.

I know that the 110 ac is not working ... perhaps I'll backup from there.
order: 1) chase ac wiring to dc to ac converter (univolt is only ac to dc, right?) ... establish that that wiring isn't shorting
2) check dc to ac converter (where do I find that?)
3) chase dc wiring to batteries

[nums]

oops! no DC to AC converter

instead dc wiring is run in parallel to univolt

troubleshooting that

[bkahler]

Sounds like the outlet the univolt plugs into is turned off or tripped. Check to see if all the circuit breakers in your main 120 volt electrical panel are on and not tripped.

I'm not sure where the main 120 volt electrical panel is in your coach but it's usually in the back under a bed somewhere.

Since he was pushing buttons everywhere he might have turned on to many things and once so I'm betting the breaker is tripped due to overload.

Brad

[crazeevw]

Originally Posted by nums

I also went through the fuses in the glove compartment. They all seem intact.

I think the problem may be related to to the step ... he did announce to me that day that he found the automatic step up/down switch (button on door frame near hinges). So, he probably pushed it 500 times. Perhaps related, the step is now not retracting ... either under motor power, generator power or with univolt properly powering other DC wiring (via 110 extension cord).

I'm comfortable using a multi-meter to measure current ... less so chasing unpowered lines.

I know that the 110 ac is not working ... perhaps I'll backup from there.
order: 1) chase ac wiring to dc to ac converter (univolt is only ac to dc, right?) ... establish that that wiring isn't shorting
2) check dc to ac converter (where do I find that?)
3) chase dc wiring to batteries

Even with 500 times pushing on that switch for the electric step, switch should be ok. I'd check the step motor before I'd start going too far. Might just be that simple.

[gaiaenviro]

My univolt was on a switch for the outlet. Might check for one down low (mine is right above the floor under the drawers and microwave). Mine has been accidentally turned off enough times that I labeled it (on/off) with a sharpie so I can see it and correct immediately as necessary...


-Bill
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[gaiaenviro]

Also check the magnet on the door for the step switch. I've found mine misaligned and spent hours trying to sort out the step (as I'm trying to leave on a trip), only to discover it's really something simple....


-Bill
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[John Woodrow]

Check your grounds. There is a 24" strap from the battery drawer to frame and one from the rear of the left engine head to frame. You probably have another issue from what you described but ground issues in our older units cause all kinds of problems.