Why Is My Engine Immobilizer Light Flashing?

[Bugdoo]

I've been searching through the old and new forums and haven't found much on this question, so I'll ask here. Over the past month or two, my engine immobilizer light has occasionally flashed at me just afer starting my New Beetle. It's happened maybe 4 or 5 times.

As soon as I notice it, I turn off the car quickly, sit for a moment, turn it on again, and all's well. I'm concerned that I might end up stranded somewhere if I have a real problem.

My NB is a 2001 TDI with automatic transmission. The keys are the originals that came with the car when I bought it new. They've never been reprogrammed. They have their original batteries. (Could the flashing light be an indication that the battery in the key is failing after almost 5 years of use?)

Anyone experience this problem and know what likely causes are?

[hannaco]

There is a code reader that reads the chip in the key. If the code is good, the car runs. If the code is bad, the car stops after about five seconds.
If the antenna to the code reader is going bad, it will fail to read the chip the first try.
The problem with an intermittent like this, it will show up as nothing wrong at the dealer until it fails completely.

[GatorBeetle]

Fun....sounds like a typical VW issue...nothing to do until there is a fatal error.

[hannaco]

Yea, you got that right. I just hate intermittent problems. Because you just end up looking like an idiot when everything checks out OK. Then, when they do fail, the only option is to have it towed into the dealer.
Sometimes a little less cutting edge isn't a bad idea.

[Bugdoo]

For anyone who might want to know what this problem turned out to be, it was diagnosed last week as a "sporadic open circuit in the instrument cluster." For once, the dealership was able to identify the problem right away. The entire instrument cluster had to be replaced and the keys reprogrammed (to the tune of $623 in parts and labor). The bug is working fine now, at just over 140,000 miles!