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Hey guys I have a problem with my battery. When I turn my car off and leave it for a while (lets say 4-6 hours) I have to come back out and jump start it. Everything is off in the car. I took it to Advance Auto and they tested the battery and it6 came out the battery is fine...they say I may have a short somewhere...I have an aftermarket stereo, and a viper alarm system. I do not know what could be causing the problem. Has anyone else ran into, any help?

check to see the alternator is working, voltage across battery terminals should be more then 14v whilst car is running.

how long ago was the stereo/alarm installed?

what was the most recent work you have done to the car?

I took it to Advanced auto...they tested the battery and the alternator there...and they both tested fine...my pioneer premier car stereo was installed back in 2006, and the keyless entry viper car alarm was installed back in 2003. I wouldnt think it would be the altenator because I can travel great distances without any problems...its only when the car is sitting...like this morning...it has been sitting over night...I have to go to work in the next 20 minutes...10 of those minutes will probably be used to jump start the car.

So you havent messed with any thing lately or had any work done? Dont know if it will help but check the fuses. It may show if there is an issue somewhere thats not obvious.

Steve-O

the only thing I can think of is the alarm...I have a proximity alarm on my car...also, if I leave the car off for a literal 5 minutes with the lights on the battery will be dead...1st time this happened it happened at Domino's...this weekend I am going to swap out my positive and negative wires for the battery, and disconnect the alarm to see what happens...I had problems in the past with corrosion. This morning I was barely able to start it with 9 to 10 volts. I appreciate the help, if you can think of anything else let me know...I will report everytime I crank it up. I will check the fuses when I get off work today. I hope is as simple as changing a fuse.

Could also be a starter motor or bad cable connection to the starter that is creating difficulty starting? Happened recently on my MX-6. 1st time I ever had a starter go bad that way in any car. Thought it was a recurring drained/bad battery for a couple weeks til fig'd thing out.

It's very common for fubarred remote starter and alarm modules to cause current draw. Like you said, disconnect all the harnesses from the module under the dash, and see if it makes a difference. The brains aren't cheap to replace though.

Good luck.

Yeah man I had some issues with a dirty terminal. Take a dremal to it and clean it of with a wire attatchment or a wire brush. I had an issue like that where I couldnt get the battery to charge and I put a charger on it and it said the battery was bad on slow charge but was fine on quick charge. Didnt even look dirty but after I cleaned it it cranked up fine. Hoppefully its something so small.

Steve-O

id check alternator twice. Id take it off the car and have it tested separate. Had pretty much same problem on my cousins civic. We took alternator and got a new one and remanufactured one was bad too!! so we exchanged that one and 2nd one is working so far.

Well I have started the car and took the battery out and the car sat and ran like a Champ...so I am thinking it isnt the alsternator, unless the alternator is doing what it does to keep the car running but isnt charging properly. I am grabbing some new terminal wires tonight and I will swap tehm tomorrow morning.

One other note...If I drive the car to work (15 minute ride) cut the car off, then immediatey start it up... it will crank up like its a fully charged battery. But let it sit for about 2-3 hours and it gets a sluggish start...3-6 may not start at all.
And if I let it sit with the engine off with the headlights on for 1 minute, it will have difficulties starting.

Definately a dud battery then, does the car sit unused for any length of time?

Take it to a different shop (or auto electrician), explain what is happening, get them to test it, it should be able to be replaced under warranty if the battery isn't too old.

Aston you were right...the battery actually looked like it was about to explode, well it was warped real bad at the positive terminal post. Luckily it was still under warranty...After putting the brand new battery in no hard starts. Makes you wonder if their battery tester will always read "Good Battery" just so you cannot take advantage of the warranty. Thanks for all the help fellas.

If you have a voltmeter, you could measure the current draw on the car, just put the meter inline with the Negative wire, and measure the amp it's using.