TheSamba.com :: View topic - Parasitic drain, narrowed it down to one circuit?

Fri Aug 23, 2013 3:50 pm

My 85 Westy has been sitting pretty much unused for a while now. Maybe once a month or so, I'll take it out for a 30 minute drive just to keep it from deteriorating, but the rest of the time it's been just sitting under the cover.

For all of that time I have had 120V plugged into the side of the van. I have an onboard battery charging system that charges the house battery first, then it relay connects in the starting battery and tops it up. Both batteries are in good shape and have been load tested good.

So, here is the issue. If I leave it off the charger, the relay disconnects the house and starting battery circuits. My house battery stays charged, but my starting battery slowly goes down. Today I hooked a multimeter up to the neg post of the battery and to the (disconnected) neg cable. Can't remember the reading, but I was getting a draw. I began removing individual fuses to see if I could narrow it down. I think I did.

The circuit that powers the wipers and blower motor. When i disconnected the fuse, the ammeter dropped to zero AND I could hear a relay clicking as i removed/inserted the fuse!! AND, another discovery!! Both my wipers and blower motor apparently are "hot" with the key off!! That ain't right, is it? in other words I can turn my wipers on/off and my blower(s) on/off without even having the key in the ignition.

So, being the electrical dummy I am, where do I go from here. How do I trace this fault?

Fri Aug 23, 2013 6:32 pm

The relay that is clicking is stuck on or is being fed by 12v batt instead of key on 12v

Fri Aug 23, 2013 11:19 pm

if it's clicking it's working properly, theres an issue with the trigger to the relay.

I'd guess something between the ignition swith and whatever triggers the wiper and blower. Have to look at a schematic to be sure.

Sat Aug 24, 2013 4:26 am

The relay you hear is the Load Reduction Relay, it is triggered off of the "X" circuit on the ignition switch. The "X" circuit also supplies power to the headlight switch so if you have messed with your headlight by adding relays and such you may inadvertently be powering the relay when it should not be powered.

Sat Aug 24, 2013 9:13 am

You just prevented your Westy from burning to the ground.

Sat Aug 24, 2013 9:13 am

You just prevented your Westy from burning to the ground.

Sun Aug 25, 2013 7:25 am

euromog wrote: You just prevented your Westy from burning to the ground.

Well, I don't know about that, I'm not done yet!! :lol:

I did do headlight relays, but that was YEARS ago, I wonder if I've had this issue that long. Honestly, I'm a little anal about keeping the batteries on the charger, so I guess it's possible.