In my 2000 z28 with 20000mimy batt seems to be draining over night. It was happening about a month ago then I took batt to SEARS they tested it chrged it up and it tested out good. I got it about a yr ago its an Optima RED top. The alternater is fine due to the car starting right up and no signs of it stalling out after start. The alternater also checked out good at the garage. Now I do have a custom system as well as anti theft keyless installed. That has been in the car for some time now. I cannot fugure out the issue and its drivin me nuts. My question is has anyone had any issues with a keyless or a custom system. Any suggestions? I do plan on takin it back to my install guy to have him look into the system and keyless though

 

Who installed your system.. Most time what people do by mistake is hook up their amp to a constant power source. Something is drawing off your battery. Use your fuse box as a helper. Pull your radio fuse at the end of the day. If your car starts the next day, its something in your system. If it doesnt, well you can figure that out from here.

 

so what after market products have been installed on the car, if it drains over night its not going to be the altornator, if it was the altornator you would tell by your volt meter, your volts should run from 14 to 16 on your dash if its not there then you need to uninstall the after market products till the niddle goes to that range, it wouldnt be your computer system either, your car has to sit for a long period of time before that complete ly drains your battery, unless you got a short somewhere...

but yea, i would take the after market products off first, and see what happens, im in electrical right now so i can ask for you on monday, then hit you back up

 

I had a Mustang in the shop with the same problems. It turned out to be the keyless entry module. For whatever reason, it parasitically drained the battery in a matter of 12 hours. After replacing the module, it no longer drained. Also, the Mustang had an aftermarket sound system that was installed by the owner.

 

Well I took it back to SEARS to have the battery tested and tested BAD. They replaced my OPTIMA red top with a DIEHARD PLATINUM which is a higher end battery and now has an 8yr warranty. They did replace under warranty so that was good. Although I am going to still test draw's and fuses. With both the after market sysytem and keyless anti-theft system I think I should still check what do you think? I already un-hooked thekeyless module and noticed that one of the connectors was melted through. Dont knowif that is it but I am going to start testing tomorrow.

 

if it was melted that was your short, and probably the problem, whats your cold cranking on your battery if you got a sound system in it you need something with 700+ in it, i recommend the duralast gold wit 750 thats what i got and i dont have any problems

you need to add a circuit breaker to the one that shorted after you replace the wiring that way if it shorts again the circuit breaker n fuses will shut it off, and it wont drain your battery

 

the die hard platinum has 880 cold crankin so its good. Yeh i gotta change out that wiring good call with the breaker forpossiblefuture issues.