The 89 SE is giving my son some trouble. Something seems to be intermittently draining the battery overnight. We disconnected the negative cable & hooked up a #90 light bulb (map light) between the cable & battery. The bulb lit up. I would say it was 60 -70 % of its normal brightness. While the light was on my son pulled each fuse from the driver'* side panel but the light never went out. We then connected a multimeter to get an actual measurement. I had to go up to the 10a scale to get a reading - .67 amps.

We still need to go pull the fuses on the passenger side but wanted to see if anyone has any ideas. The power antennae has been disconnected for years.

Ted, That .67a is quite a significant load on the battery as I'm sure you know. (16 amp/hrs every 24hrs.) It represents approximately 80 watts of power coming out of the battery continuosly. I'd continue with fuse & relay isolation which is what you have already started. I'll be anxious to see what the culprit is. Good luck with it.

Played around with it some more yesterday & couldn't find anything wrong. We decided to go over to Autozone & get the battery checked. Sure enough the battery was bad. They gave us a new battery under warranty, the old one was only 16 months old. Started fine this morning. We'll see if it gives us any trouble this week.

That'* a big load though...

Was that hood light
Radio and anything else drawing power still?

With the new battery it'* now showing even more of a drain - 1.25 amps.
Could old batteries in the meter affect the readings?
Has anyone else tried this & know what their reading was?

Edit - Hood light & radio were off.

The '93 peaked at .05A and seems to like to sit at .03A.

My sisters' '90 Olds 88 Royale sits steady at .03A also.

That is a significant drain. I wouldn't think the meter battery would cause the reading to vary that much. Any after-market stuff that may drawing it down? Maybe even something buried? Glove compartment, and trunk light, if equipped, shutting off properly?

The meter is 7-8 years old & still had the original batteries so I decided to change them just to be on the safe side. After opening it up I found one of the 2 fuses were blown. I'll replace the fuse tomorrow & recheck.

Damemorder - thanks for checking that. If I get the same reading tomorrow I'll know we have more work to do.

Archon - Radio was replaced about 2 years ago & I help him install some cheap after market foglights a few months ago. Foglights only worked for about a month. Glove & trunk lights were checked.

I put a new fuse & batteries in the meter & worked on this a little more today. I think the glove box might have been opened when we were getting the 1.25 amp reading. I didn't really know what to try except go back over what we alredy did. I don't know how we missed it during the 1st check but we went from .7 to .02 amps when fuse #15 was pulled. So we have it narrowed down to a problem with the courtesy lights , power mirrors, door locks & possibly the fog lights.

The doors aren't open when you are testing fuse 15, right?