Tracking down electrical gremlin

Wife's '01 Camaro has been acting up lately. Very hard to start in the morning. I've had to put the charger on it every night. The battery and alternator are fine, according to the Advance Auto store guy.

I have a vague recollection of a method to track down electrical draws with a multi-tester, by pulling a fuse for each circuit and watching for the meter to change. However, I can't remember the exact procedure.

Any input?

First, be sure everything that can be turned off is. Then put an ammeter in the circuit between the battery ground post and the ground cable. Now go have a cup of coffee, because modern cars will often take up to an hour for all the modules to go to sleep. Following nappy time, you should have less than 40 milliamps of current. If more than that, start pulling fuses one at a time, and watch the draw on the ammeter. When it drops below 40 ma, find a wiring diagram and figure out what all that fuse powers up, and start disconnecting those components one at a time.

Remember to set yourself up so you can access the fuse panels. If you need to have a door open, trip the door switch to shut off the interior light. Don't turn the key on, or you have to go through the nappytime deal again. As a matter of fact, when you pull the fuse that supplies the keep alive memory for the various modules, you may have to make it go nappy again when that fuse goes back in.

Have fun. If it turns out to be a body control module that is powering things, find yourself the very best GM electrical guy, and his Tech2, in the world, and pay him what he asks. It will be worth it, as there is no backyard way to reflash those modules.

Thanks, I'll give it a try.

How old is the battery?

I have recently had a battery take a charge and test "good" at Autozone. Took it home and put it in the car and the car started fine. Next morning, not enough juice to turn over. Checked the purchase date on the battery and my 60 month battery had gone 72 months. Put in a new battery and that fixed it.

Easy way to tell if it is the battery or a draw. Disconnect the negative terminal on the battery. Let it sit overnite, reconnect the neg. cable, see what happens.

mcp001 wrote: How old is the battery?

A little more than a year old. I pulled it out of my old, beater truck that would start on sub-zero mornings, after sitting, unused, for a week. The battery from her car went back into the truck, and also would start it on very cold (no sub-zero days this season, yet) mornings after sitting ununsed for a week.

iceracer wrote: Easy way to tell if it is the battery or a draw. Disconnect the negative terminal on the battery. Let it sit overnite, reconnect the neg. cable, see what happens.

I'll give that a try. The ammeter we have at work is... fussy. Sometimes it works, sometimes it doesn't.