Hey everybody, I need some clarification so I can chase down my electrical gremlin. The problem is my battery is draining down over night, alot like a circut is being left on. It takes about 6-8 hours for the battery to go D-E-A-D, DEAD. The cabin light doesnt even try to turn on.

History. Had the car stored for 8 months, battery went dead and was replaced. With the new battery, I was able to start the car with ZERO issues 5 times before I started making changes to the car.

Now for what changed. I just took the heads off my car and changed them out with some aluminum ones. With that, I no longer had the ground points on the back of the cylinder heads. SO. I grounded the driver side ground wires that were coming out of the wiring harness to the firewall, then I grounded the passenger side firewall ground to the passenger framerail by the control arm. Also I removed the A/C system, blower motor and smog pump. And all the wires are disconnected and tied up to the side.

Now other than those things NOTHING has changed.

Ideas? Also I need to know where the grounds coming out of the harness behind the block come from.

 

anything that requires power i would check the connections to, get a voltmeter and try to go thru everything, with the car off, even your radio.

with the car off see if u here anything also, any humming

 

Well although electrical shorts can be a nightmare to track down there is an easy way to go about it. First you need to measure the current draw while the cars off and everything is off to the best of your knowledge. There should be very little current. Because there wont be in your case write down this initial current measurement and pull fuses one by one and re measure the current draw. If you pull a fuse and see that the currnet draw drops thats the circuit that has the short and then you troubleshoot from there.

 

I'm pretty sure you can check to see that their is some draw without the key in the car by putting the ground of the voltmeter onto the positive side of the battery and the other end onto the negative side of the battery.
My Trans Am had a horrible draw, I chased everything and pulled every fuse I didn't need and it was even draining with all the fuses out of the box; I ultimately failed at finding what was causing it so I put a cut off switch in the car.

 

Well couple things first if you set your volt meter up like that you'll just read battery voltage (but negative). To measure current you actually have to break the circuit. As far as your short goes even if you pulled all the fuses and still had a short that narrows the possibilities way down. If you wanted you could start a new thread and get to the bottom of it but if your content with the cut off switch thats fine too.