[abc123]

Hi,

I have 2000 VW Jetta that is having immobilizer problems (again). About 5 years ago, the immobilizer would start to randomly engage. I would then have to have it towed to the dealer, have it reset, etc. This happened about 4 times over 2 months. I then spent about 1100.00 to have it fixed and the problem seemed to be resolved.

This morning the immobilizer engaged again and so I tried unlocking/relocking the doors a couple of times and then let it sit for a few minutes. I then tried starting it with the plain key and it worked.

It may be a battery problem with the battery key and I am going to replace the battery tonight. However, if this happens again, I want to be prepared with tips on how to fix this in case I'm out on the road somewhere. I don't want to have to tow it back to the dealer every time it needs to be reset and pay them to fix.

At this point, I don't really care if the car has an alarm or not.

Thanks.

 

[chittychittybangbang]

The battery in the key has nothing to do with the immobilizer at all. Once you take it apart you'll see the immobilizer chip isn't connected to anything. Read the mk4 Key FAQ for pics and more explanations.

The battery in the car to start the engine can trip the immobilizer if it's low. If it's acting up again, check for electrical problems like bad grounds, coolant migration, or bad antenna around the ignition cylinder for the immobilizer.

 

[BMWnugen]

Chip tuning can remove the immobilizer. Like chittychittybangbang said, it wouldn't be much of an anti theft device if it was too easy to remove!