Hi all,

Recently my relatively new (6 month) battery died overnight. It had been fine up to that point and was being maintained reasonably well by an aftermarket alternator (claimed 120 amps, whined a bit but finally settled down).

When I say "died", I mean REALLY died! It was down to around 7 or 8 volts and 3 attempts to charge it failed, plus my battery tester declared it "bad".

Long story short, a trip to the auto parts store, where they did their own testing and claimed it was taking a charge but was only at 25% capacity. I insisted on a replacement and got one!

Installed it and all was good. Or so I thought.

While I was inside the car after running it a few minutes, key off but still in the ignition, resetting the clock and trying to find my radio code...

I noticed the rear heated window button orange indicator bulb was illuminated. That's odd. I hadn't switched it on. Didn't think I'd been anywhere near the button, in fact.

Tapped the button to turn off... Still on. After several tries, it finally turned off. Weird. Maybe I had just inadvertently switched it on.

Then a few minutes later it came back on! All on its own! I know for sure this time I hadn't touched the switch.

Turned it off again... and, sure enough, a few minutes later it turned itself back on again. Okay. I think I know what killed the battery!

Anyway, I pulled out the switch and unplugged it. Maybe it just needs a good cleaning?

But I still heard a couple faint "clicks" from that side of the dash and thought there might be a relay in there switching itself on. So I pulled 30 amp fuse under the hood, which appears to only power that rear window heater circuit (incl. the exterior mirrors and the rear, side windows, as well as the large window in the door).

Anyone seen anything like this? Have any suggestions where I should start looking for a fault? I will be cleaning the switch with DeOxit, but doubt that will make any difference.

I can't remember ever having circuits mysteriously turn themselves on in any car before! This is a new one! Lucas, Prince of Darkness, has really outdone himself this time!

Thanks in advance for any advice you might have!

Alan Myers
San Jose, Calif.
'97 Disco SE7
'62 Triumph TR4

 

You probably have water that may have leaked into your fuse box located on the driver side under the steering wheel cover above your kick panel. It can cause all kinds of problems.