Here's a weird one...got me head scratchin'

[dznf0g]

In Florida, last week, we had a monsoon-like rain with a driving wind. Good news--only one water leak alarm went off on the curb side rear where the shell meets the flat side. Small leak, carpet not wet, but gotta find it. Here's the weird part. After the rain stopped, I went out to the truck and turned the ignition on....the rear camera (AS) screen popped up with a view from the rear of the trailer! Mind you, the camera is powered off the running light circuit and the umbilical was not connected. The running lights were not lit. Now, I realize that the incandescent filiments need high current to even glow a bit and the camera needs only about 200mA to operate, but the running light circuit is 100% dedicated and has no common 12 volt feeds with any other circuit, that I can conceive or know of.

I suspect that the leak is connected to this phenomenon, but I can't see how. As soon as things dried out, all was normal, until another big rain shower, then same thing. Now, all is normal. Umbilical connector was protected inside the propane cover and appeared bone dry, both times.

Where's the 12V coming from?

[A W Warn]

I would still bet on the umbilical cord or connector, since that is where the positive on the charging circuit and the running light circuit wires are in close enough proximity to almost touch.
Corrosion, dust, or trash, dampened in the high humidity, could carry that small amount of voltage.

add edit:
A spider web in the 12v fuse panel might also transmit a small voltage, especially if damp.

[dznf0g]

Both good ideas! Thanks. It was certainly humid. I'll hit the connector with some contact cleaner. I just went out and took off the side panel in the bedroom and everything is dry to the touch. Removed the water alarm probe and my sweaty fingers set it off. Reinserted it in the floor and it didn't go off. The Doberman alarm is really sensitive, as far as alarms go. That leak must be TINY to be already bone dry.

[garry]

The camera could be receiving it's power from the trailer battery due to a wet connector at that end (male side of the connector).

Next time it happens disconnect the AS battery.

[dznf0g]

Originally Posted by garry

The camera could be receiving it's power from the trailer battery due to a wet connector at that end (male side of the connector).

Next time it happens disconnect the AS battery.

My first thought as well, but the marker light circuit is always dead, in the AS and the TV until the TV park lights are switched on. There would have to be a 12V to 12V cross circuit short for that scenario it even be conceivable.

Also, if you mean the connector at the positive junction box, where the umbilical terminates to the AS wiring, it is inside mounted on the electrical center about 8" off the floor, in a plastic box. No water there.

[wolf146]

Originally Posted by dznf0g

Both good ideas! Thanks. It was certainly humid. I'll hit the connector with some contact cleaner. I just went out and took off the side panel in the bedroom and everything is dry to the touch. Removed the water alarm probe and my sweaty fingers set it off. Reinserted it in the floor and it didn't go off. The Doberman alarm is really sensitive, as far as alarms go. That leak must be TINY to be already bone dry.

DZnf0g - How did you get the side panel off in the bedroom? I have a 2004 - 30 foot classic and can't get them off to check for leaks. Wolf 146

[dznf0g]

Originally Posted by wolf146

DZnf0g - How did you get the side panel off in the bedroom? I have a 2004 - 30 foot classic and can't get them off to check for leaks. Wolf 146

SEEK and ye shall find....two long screw heads in the carpet nap. A magnetic stud finder would help. There is probably no rhyme nor reason to where they are, as I am sure the assembler just puts them wherever. Hang for a few minutes and I'll go take a pic.

[dznf0g]

Here ya go....





Just be sure not to over tighten when reinstalling. The inner skin is all that holds them. Easy to strip.

[wolf146]

Thanks for the info about the side panels. I'll check it out. Wolf146

[garry]

Just trying to help here. If the AS was NOT connected to the TV then the voltage has to come from the trailer battery.

You can test this by shorting the AS battery +12v to the trailer charge line at the umbilical that should turn on the running lights and the camera. Same thing is happening when something is getting wet and shorting out just enough resistance to not turn on the running lights but enough to power the camera.

I think it is pin 3 to pin 4 on the trailer side. This may not be the problem but the only sourse of power is the trailer battery.

[dkottum]

High resistance short as described by garry sounds likely to me.

Could your moisture be coming from condensation within the trailer rather than a leak, I've seen it with our Moisture Test Meter in the subfloor.

[cwbiii]

Somewhere there is usually a hatch that gives access to the point where the trailer umbilical is wired into the internal wiring for the lights on the trailer. In older AS it is underneath in the belly pan. This is one other place where moisture could cause the high resistance short you are talking about. Anywhere else that camera power wire runs inside near to a power wire is a potential cause for this if water enters the picture... even inside the camera unit itself if it has a connection to trailer power and uses a signal wire to turn it on.

Chuck

[cwbiii]

With the umbilical cord put up inside the propane cover, the water can follow the umbilical if it is all downhill into the box where it ties into the main wiring... or their could be a nick somewhere in the umbilical that the water is causing the high resistance short across.
Just a couple more possibilities to check.

Chuck

[dznf0g]

My umbilical comes through the floor, intact in it's black sheathing. Completely sheltered from the weather. once inside, under the sofa, the individual wires terminate in a positive junction block encased in plastic box 6" up off the floor. Can't be that end. Could be the truck end connector, but it was up inside the propane cover...not that enough moisture could not have gotten to it, I suppose.

It's fine now, but I have a trip next week and a bit of rain is in the forecast. We'll see. Could be much adieu over naught.

[Al and Missy]

If there is a high resistance short between the trailer battery and the camera/running lights, it is unlikely that there is anywhere near 12 volts on the wire. But if the camera has an internal regulator with a lot of overhead, it might still work. Be prepared to measure the voltage at the umbilical or one of the bulbs the next time it happens.

Al