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Discussion Starter #1 (Edited)
Help! Car immobilizer wont' let me start it.

Well, I've had all the usual electrical gremlins that 2000 Passats have: doors unlock and unlocking will, alarm going off by itself, etc. Now however, I can't even use the car because when I put the key in the ignition, the alarm sounds and the car wont let me start it.

I've researched the problem and it seems dishearteningly complicated. I've read that the CC Controller mixes up signals from the hood latch and the radio, that the door micro switches can cause alarm prob mes etc. Even a bad ground to the radio.

Another problem is that my VGA COM can't access the central locking or immobilizer controllers--where I assume I would want to start the diagnosis. I've had some trouble with VAG COM before so maybe I should reinstall it. Or is ti possible that if a controller is bad you just cant access it?

Anybody can give e me a idea where to begin?
 

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NO. ECU has nothing at all to do with the alarm in a 2000.

If the alarm is going off, then it's not being disarmed. Does alarm light on the driver's door continue to blink even after unlocking the car? Do the interior lights come on when you open the door? If you are using the key in the driver's door to unlock the car, try unlocking from the trunk or passenger side (if you car has pass. side lock cylinder, not all do). You may simply have an issue with the driver's door lock mechanism, so the car electronics don't know that the car has been unlocked.

If that doesn't get around the issue, then you'll have to inspect the CCM and the splices in the wiring harness between it and up to the kick panel area.

Your car doesn't have an immobilizer, so it will not register in vag-com. Central locking will be #46, so if you're not able to connect w/ that module, then the CCM and wiring is even more suspect. Since the door randomly locks & unlocks, you most likely have a problem with the door lock module (possibly in addition to CCM issues) Look here for lock module repair: http://www.taligentx.com/passat/maintenance/doorlockmechanism/
 

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Discussion Starter #5
Thanks SG Bob. Even before I got your post , I had decided to check out the Cent. Conv. Module. It was full of water. (I shd have mentioned that the drain hole under the battery got plugged and the driver's side flooded. That issue has been since addressed.)

Anyway, I pulled it all apart and dried the circuit board and connectors with a hair dryer. Amazingly, after plugging it back in, I can start the car.

But I still have question and issues. For one I still have a fault code that says "the Cent. Conv System bus is in emergency mode." What does that mean?

Also, my remotes no longer work at all. And I can’t access the Cent Locks controller. Where is that sucker so I can have a look at it, too?

Thanks SG Bob, again. I’ve been finding a lot of your posts as I research PW on this and related issues. I appreciate your efforts.
 

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The CCM is the central locking controller in your model - all of it is accessed thought ch 46 in vag com. You probably have some failed splices in the wiring harness - there are several between the CCM and up to the kick panel area. You have to peel off the bundling tape and separate out the wires to see them all, as some will be buried inside the harness. Any splices that don't look clean (bare wire & metal) should be redone. You may also have some bad wires - they rot from the inside out if they're left laying in water long enough. Tell tale sign is green residue on the wiring jacket, which is actually oxidized copper that has leached through the jacket.

You may also have a failed CCM. Was there any rust/ corrosion on the circuit board?
 

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Discussion Starter #7
Doh! I knew that. Actually as soon as I read your comment, I looked back at my notes and realized one of the firsts thngs I did when I bought the car was to use VAG COM to reprogram the locks--through the CCM. Dumb of me.

Anyway, it's all academic now, since now everythng is working again. BTW there was no evidence of corrosion in the circuit board or pin connectors--but who knows waht faults ther might be that are not apparent?

Thanks for all your suggestions, though. I'm sure I'll be using them again some time!

One last question, dews anyone know what that error code---"CCM Bus in emergency mode"--means?
 
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