The Project Pad

Hi guys, I have a new problem on my 92 UrS4. I started to notice after a few days (3+) of not starting her that she would be slow to crank about a year ago. I sense replaced the battery hoping I just had a battery issue. I then went on vacation and came back a week later and I had no power at all, 0 volts registered. Charged her back up and she was fine till about 2 weeks ago when she sat for 2 1/2 days and I went to start her up and there wasn't enough power. I charged her up again and used her every day till this last weekend when I let her sit for about a day and a half. I went to start her up again last night and she didn't have enough power to start again. I charged her up and verified voltage at the battery was 12.5v and let her sit over night.

This morning, about 13-14 hours later my battery won't start my car again, measured at 8.8v. I've verified nothing is set to on right now, no lights, heated seats, ect.

So, something is going on. I charge her up again to 12.4v, disconnect the negative and put my multimeter in line on the ground and set to 2A, non-fused (this cheap one doesn't have a fused Amp reading). The readout on the meter goes to " -1 " (-1 on the far left of the readout, not where you'd expect it or not 1.00) immediately and the wires get noticeably hot within 10 seconds. Does that mean that the drain on the battery is greater than 2A? The readout doesn't fluctuate at all, just stays the same and jumps up to there right away. I've already disconnected the aftermarket stereo (amp and head unit) because I wanted to make sure that wasn't it what I did.

So am I reading this right and the meter is pegging out at above 2A? Does my meter just suck? Any ideas what could cause so much drain?

In for curiosity because I had a similar problem on my 200 before I sent it up to Marc... sorry I can't help more, but here's to wishing you good luck!

Make sure the light in the trunk isn't on all the time. That's what happened to my 80. I pulled the bulb, and haven't had a drain issue sense.

I had the same problem. The switch for the trunk light was not acting right. The way I found out was by removing the ski boot shutting the trunk and seeing through the rear arm rest/ski boot that the light remained on even with the trunk shut. I got another switch and the problem was fixed. Not saying that's what you have... but worth checking into.

Pulled the light bulb in the trunk and I am reading .38 Ohms... Thank you guys for the help!

And an update...

I am loosing about .8 volts per 12 hours, something is still just not right. I'm actually at -3.8 Ohms when I set it to 200m.

The light bulb is pulled out in the trunk, the lights are all out on the car (verified tonight) when the car is off.

I'm planning on pulling fuses one at a time tomorrow just curious if anyone has an idea on what to start at?

Have you noticed anything weird like the windows still working after opening the door? Does the central locking work? I have a similar issue but my car doesn't seem to register when the drivers door opens, at least on certain circuits. The footwell lights will turn on and off so I know the switch is working

Weird, now my car is draining the battery per normal. I'm sure at some point in the future I'll go out and she'll be dead again and then I can start looking for the culprit again.

Thank you all for your assistance.

Mine too - Let's all figure it out and post why here haha.