electrical drain

[jettajz]

I have a 2000 Jetta 2.0

My problem is what appears to be an electrical drain on the battery. I have always had a slight problem with the car not starting after letting it sit for more that 24-48 hours but now it will not start after about 8-12 hours. I have tested the battery and that appears fine. The alternator is not the problem because it always recharges after it is run. I have no experience in electrical diagnostics but I always like to do it my self. After reading a few threads in this and other forums the ideas I have come up with are:

A light was left on - Not the case I have checked and rechecked everywhere.

The Starter Silenoid (sp?) is bad - a possibility but I have no idea how to check it.

There is a bad fuse draining the power - again, a possibility but I have no idea how to check it.

Can someone point me in the right direction on how I can check these possibilities? All I have at home is a battery voltage tester so if I need any other tools please let me know when you inform me of things to check.

Also - the car starts and runs fine with a jump

Thanks and I appreciate any help you can give

[skeeter111]

do you have a cd changer in the trunk? if so try unplugging it and see what happens. if the problems goes away then you have a bad cd changer which is very common on vw's. you can either leave it unplugged or buy a new one. if that doesn't fix the problem then you will have to do a current draw test.

[jettajz]

Nope, I don't have a cd changer in the trunk.

[veedubmechanic]

do this... after the battery is charged from driving if you have an amp meter you can check current draw. (many sites on line can show you with pictures how to check with meter)

just open the driver door and use a screwdriver to close the latch (making sure the light goes off) and start pulling fuses. Once the reading goes to 0 or close to 0 then you know what circuit the draw is on.

[jettajz]

Thanks, I'll give it a try

[texasjettaowner]

I am having the exact same problem with 2001 Jetta and it is driving me nut's. I have been a mechanic for 25 years. Here are a few bsisc things I checked first on mine. Even if the alt. is charging fine you could have a bad diode and it is leaking back. You will have some draw on your alt. all the time but if a diode leaks it can create battery drainage. Normally you will here static or whining noise in your radio. A sure test is after the engine has cooled down when you touch the alt is it still hot if so replace or repair it. Second thing is when you get home listen and see if the cooling fans shut off after a few minutes. I saw this happen on my wifes Passat. I also discovered that Jetta are famous for brake light switch failure I have already put 3 on my 2001. VW has been real good about replacing them and no cost. Normally if your have a automatic you will see problems in the shift lever first not releasing. Last but not least heated mirrors I went out to the cart one morning and the car had ice but the mirror was clean and clear when I thoched it it was warm. Make sure your heated mirror switch is off (if you have it) when not in use. I hope one of these helps you now if I can only figure out my problem.
Good Luck