Hi all, I'm new here and hoping that somebody can point me in the right direction with this issue....

2002 Intrepid 3.5L V6

I'm getting multiple codes from the OBD as follows:
P0340 - Camshaft Position Sensor Circuit
P0344 - Camshaft Position Sensor Circuit Intermittent
P0441 - Evaporative purge flow system not working properly (this one does not always come up when I run the OBD)
P0513 - Incorrect immobilizer key ???
P1686 - No messages received from the smart key immobilizer module
P1687 - No messages received from the mechanical instrument cluster module
P1695 - No messages received from the body control module (this code always shows twice then I run the OBD)
P1698 - No messages received from the electronic transmission control module or the aisin transmission controller
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I was driving and got stuck in heavy rain when the problems started occuring.

When I turn on the ignition key, everything appears to be working just fine. Start the engine and everything is fine for about five to ten seconds, then the guages all go dead and the dummy lights all come on. The ventilation always changes to defrost and is not controllable, occasionally turning the heat up to full blast but never blowing
cold air (which sucks with Florida Summer lol).

I had a bad battery so that was replaced. Alternator was checked and output is perfect. Here is a wrinkle to my mystery, If I start the car with the alternator unplugged, everything works perfectly.... until I plug the alternator back in, then five to ten seconds later everything goes dead again.

I have been told that it is a bad BCM and I should begin there or take it to a Dodge dealer. I have also been told that the BCM is prob ok and that there is likely a short someplace in the system. Taking it to the dealer is not in the cards for me at the moment, as I'm sure they will charge more to repair it than the car is worth.

Should I hope the BCM is the culprit and get one from a junk yard? I've done lots of research on this and have found very little inforation on the subject, but what I have found is not very encouraging.

Any suggestions are def appreciated.

Thanks,
Ralph

 

Sounds like a short circuit to me. The no signal stuff makes me think the bus is shorting out. The bus is a comunication line between computer modules. I'd also make the leap that your altanator power output is shorting onto that line. When it's output is zero, everything is fine, start the car, power begins to generate, short on the com wires and shuts off tcm, bcm, and key mod. Of course this is only a theroy, but I'd inspect and clean the connectors in the engine compartment. Also make sure to ck the tcm plugs under the air filter. Check firewall connectors as well. Try following the power lines from the alt voltage reg and inspect all connectors along it's path (not so much the big red wire). A wet connector can be a cheap fix if you can find it! Good luck,

Kurt