This may well overlap with all or most of a range of years of Chrysler products.

I'm currently working on a friends 07 Town and Country. It was occasionally not showing either Park or Neutral on the dash and therefore not starting. At that point it was not throwing any codes regarding the security system and if there was a dash light indicating it, I sure didn't see it. We speculated that it could be the "range sensor". And I replaced it. It then appeared that it would require the "quick-learn" procedure but it wouldn't start.

I need to know how they achieved "theft deterrent" on that vehicle. If it did so by not allowing the vehicle to be put into neutral or park it would of course not be able to be started. GM usually does a starter interrupt or ignition disable. If Chrysler's way of doing it is by disabling it's ability to start by not allowing for neutral or park...well, then I've probably been going about this repair in the wrong direction.

After installing the range sensor it threw a code stating that it did not recognize the security key. It was only then that the owner mention that it had done some weird stuff like that in the recent past with reinforces my suspicion that we may not be dealing with a mechanical problem but possibly a security system issue right from the beginning.

If this were a GM vehicle, which is most of what I work on here in my area, I would know how to disable the security system and at least rule it out. But, to be honest, I have no idea how Chrysler does it.

If there's anyone on here and that has experience with Chrysler security systems, possibly how to bypass them I could at least then determine what we're actually dealing with.

All I really know about any of the security systems is that if you aren't able to disable them yourself they can be a very expensive problem.

On one GM system you simply put a resistor in the correct circuit, it reads that value more than once and, although the system is disabled, the vehicle will run and the owner and drive. If there's some similar method with Chrysler, I'd sure love to hear about it. I've all but given up trying to Google my way through a problem. The only time I seem to be able to get an answer that way is if it takes me to a forum where the topic is being discussed.

I fell bad for the guy, he needs his wheels bad. Fortunately he had an old clunker I was able to get running for him and at least until it dies, he has a way to work. But I'd really like to be able to get his better car back on the road.

Any and all help would be GREATLY appreciated.

Wayne