Community Forums

hax · 02-21-2013, 02:58 PM

Wizards of the Alpine electrical system I have a question. I had some corrosion building up on my house batteries, so I turned both selector switches to off, disconnected the ground cable connections from both the coach and chassis batteries and sprayed out the battery compartment with my garden hose. I could hear a very soft muffled click in the battery compartment. Because I sprayed the batteries off with water, I thought it might be a drip. A few hours later I went in the coach and found the transmission selector panel cycling between an * and the N for neutral. That was the source of the muffled click I could hear. The key was off, the ground side of the batteries were disconnected, yet the transmission panel seems to have found another ground source, bypassing the ignition switch. I disconnected the positive side of the chassis battery and the panel shut off and the sound went away.
Any ideas on why this panel had power with the negative battery cables disconnected? The coach wasn't plugged into shore power either. http://www.irv2.com/forums/images/smilies/confused.gif

Algoma · 02-21-2013, 03:13 PM

Do you have a solar panel?

hax · 02-21-2013, 03:48 PM

No solar panels

Wayne R · 02-21-2013, 03:56 PM

It is getting ground somewhere. Looking at the 2001 diagram on the ACA website the house and chassis batteries share a common ground. Make sure the chassis batteries are disconnected from the house side ground.

http://www.alpinecoachassociation.com/tech/tech.html#chassis

Algoma · 02-21-2013, 04:16 PM

Was the battery still wet after you washed it? It is possible there was a ground path from the post to the clamp across the center of the battery.

Paul R. Haller · 02-21-2013, 05:51 PM

You are correct, the water is a fairly good conductor of electricity and some circuit was developed between the ground post and the chassis. When all the water evaporates, I'm pretty sure that ground connection will be lost and you'll have no more tranny selector troubles. In some cars I have had I ended up with 1/2 volt through corrosion and water connections.
-Paul R. Haller-

v8dave · 02-22-2013, 03:23 PM

I have a 2000 Alpine and when I installed an Echo Charger. I experienced the same clicking you mention. Although, I did not go up inside the coach to see if anything was amiss.

I had first disconnected the negative leads, then after laying cardboard over those cables, I disconnected the positive leads and laid another cardboard insulation layer over all the leads. [You never know where a dropped tool will land.] So, I had the clicking with both battery sets switched off and both battery sets with both + and - leads disconnected. I did measure the positive line to the frame ground and found around 11 volts there. Although, in my case I do have solar panels. I opened the fuse line from the solar panels and the clicking went away.

Incidentally, after fully re-connecting the batteries and running the Cummins motor, the ABS error light came on and stayed on. A little research shows that the ABS system wanted to see the wheel sensors working and you need to drive about 5 Mph to reset the ABS system. Sure enough that is how I got the error to go away.

EngineerMike · 02-25-2013, 05:29 PM

V8Dave wins. I've only measured up to 8 volts leak to ground just on the wet looking filth on customer's batteries. Usually that comes w/some fairly rich corrosion.

hax · 02-25-2013, 09:39 PM

Batteries were dried with leaf blower. Maybe damp, but no standing water.

v8dave · 02-26-2013, 12:24 AM

Quote:

Originally Posted by EngineerMike

V8Dave wins. I've only measured up to 8 volts leak to ground just on the wet looking filth on customer's batteries. Usually that comes w/some fairly rich corrosion.

Hate to say it but I'm not the winner. The 11 Volts I measured was at house battery terminal connector on the back bulkhead. Not the positive terminal on a supposedly ungrounded battery. The 11 V was from the solar cells and it went away after I opened the solar in-line fuse carrier.