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Immobilizer Problem???

I have a '94 325i Convertible.

I get CODE on the radio sometimes. No apparent rhyme or reason. I input the code and the radio works fine.

The window -- driver or passenger door -- loses its Home Position, and thinks it is fully raised. When the door is opened, the window will drop -- as if the window is fully raised -- then go up when the door is closed. (Dropping and raising is normal IF the window is fully raised when the door is opened, but my windows will behave this way even if the window is fully down, and will repeatedly behave this way until the window actually reaches the top.) The Convertible windows work the same way as the coupe windows, the sedan windows do not have this behavior. This is a random event too. If I intervene by operating Window Switch, then the window will behave properly until it forgets where it is again.

When I set the Ignition to START, the car does absolutely nothing. I have to turn the key to OFF then START again, and it starts properly with no indication of any weakness. This is a new behavior. The first failure was noted in the radio CODE, then the windows began to do strange things, finally the ignition started to flake out.

Twice in the past 10 days, or so, the Emergency Flashers started flashing for no apparent reason, as if the car was reacting to being in an accident. These instances came about when the car was parked, and I thought my dog had stepped onthe flasher button, but the button was not depressed so the dog is not the problem.

I thought this was an indication that the battery was getting weak, but I've been told this could be a sign of problems with the immobilizer.

Reply to
Jeff Strickland
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I'd suggest you start with the battery connections, check for cleanness and tightness. A car that doesn't start and then says CODE could be a high resistance connection to the battery which is fine for keeping systems alive but is effectively shorted out when the starter solenoid is engaged.

It's possible this is a separate problem - I had this happen once or twice to my 94 325 and then, as soon as I went on holiday, it went bananas until it flattened the battery. I'm fairly sure it was the hazard relay at fault (long time ago!)

Reply to
Scott M

Sorry, I was not very clear. There is NO relationship between the occurance of these symptoms. I get CODE when the car starts properly. The only relationship is that all of these things happen randomly, and they are all related to the Crash Detect or Body Electronics modules.

Reply to
Jeff Strickland

Can you measure the battery voltage as you crank? I wonder if it's dipping just low enough to trigger the radio's disconnection detection.

Personally I wouldn't think it's anything to do with those two modules but rather coincidental failings. The radio CODE is internal to the unit so I can't see it being affected and the hazard relay is a moderately common failure. Starter solenoids do occasionally stick as they age, usually first use of the day. Again, my 325 needed the solenoid stripping down to clean as it had started not starting and needed a 2nd or 3rd attempt to get it to spin.

I'm more than willing to be proved wrong and the problems are connected, though my first check would be a stable and correct battery voltage before, during and after starting. Alternatively, dan you find spare modules at a scrapyard to see if that eliminated the problem.

The only thing I can say about the window is that the shaft encoder magnets can slip on the motor spindle upsetting their operation, though if it'd be a hell of a coincidence if both sides failed at the same time. It's a while since I looked at how the E36 system works though.

Reply to
Scott M

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