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Imobilizer Hack or Bypass !?


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Looks like I'm looking at my third immobilizer. Not sure but I crossed the leads on a battery charger and I think zaped it, everythings screwy electrically and it won't crank. (I've checked all the usual stuff; clutch switch, ignition switch, etc) I can jump a relay in the trunk an make crank but no ignition.

The immobilizer for me is really nothing but trouble. I'm the one imobilized. I'd love to simflify and be rid of it. 3 of these have cost me far more than my theft insurance deductible. With the 15+ year old tech, it wouldn't seem to be to much trouble to maybe fake a "go" signal to the DME (with a little $50 open source micro controller maybe.). Once my car is running, the immobilizer seems to be done any way, no need for the fob pill to be anywhere near the car to run and drive. Seems just a little signal during the first few seconds of cranking is what stands in the way of me and $1k in savings. So:

- Anyone find a way to anyway bypass the signal receiver in the DME, trick it, re-flash it, replace the immobilizer with a fake, whatever...

- Also, is there a way to test the transponder coil & transformer? (outside chance I mess it up working on interior)

Regards, PK

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As we rarely see immobilizer issues unless they get wet (and even then most can be dried and recover), what is causing you to kill so many?

You also need to realize that exactly what you are asking for is what a thief would need to steal your or any other Porsche out there, so I suspect a "public" response will not be forth coming...............

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You also need to realize that exactly what you are asking for is what a thief would need to steal your or any other Porsche out there, so I suspect a "public" response will not be forth coming...............

Private message/post is fine then (grin). That point also suggests it could done and in 30 seconds or less. That would be fine but I'm just as interested in a one time permanent fix, If it takes some time and energy to do a fix, so as of no use to a theif, thats fine..

As for wrecking them; At least one soaked for a week or two, Another, a new replacement, wouldn't accept another key code when I lost the key and had to replace it. This current one, I suspect, is damaged from battery charger leads being reversed for 20mins or so (I read that would do it, but if not....). As far as drying them out, I've done that a dozen times at least and worried every time it rained (till I found a fix). But here I am again and that's the point, I’ve sweat far more, & justifiably so, about it not starting and leaving me high ($$$$) and... wet, than I ever have about it getting stolen.

- If the immobilizer would be unlikely to get wrecked from reversed charger leads, let me know and I'll keep looking for the problem. (still want to get rid of the immobilizer though).;

- Also, theres a chance I tweaked the leads on the coil transponder reciver thing. Any one know how to test it?

I realize from googling this is not a new topic and has been covered (in conclusively) but it's been awhile. I know it can be done though and I'm only reviving the subject because, I don’t know how & because the cars old enough that it might be more of a common knowledge thing.


Regards, PK

Edited by pk2
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  • 3 weeks later...

Thanks, It turned out to be the imobilizer ring transceiver. Took awhile to find out how to check it but I did and that was it.

Still want to lose the imobilizer. Turns out they're not even that great at all. 40 bit encryption as opposed to the 128 bit encryption everywhere else these days...probably including this site. About 6 years ago a team at Johns Hopkins U. proved how hackable the systems were, completely.. It's annoying that anything that acts up in the car has this mystery relic in the loop.

Of my soap box, PK

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  • 4 weeks later...

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