Chrysler t&c computer bad

QuestionEdit

QUESTION: Hi Mr Finston,

Thank you for reading this.

My issue is the same as this one: http://en.allexperts.com/q/Chrysler-Repair-807/2001-Town-Country-PCU.htm I have a 2001 6 cyl T&C with alarm with 87955 miles. The mechanic told us that 4 of 6 cyls are firing, a new computer is needed then a leak down test would be needed & after all that he couldn't be sure it would be fixed. I bought a used ecm from an online parts dealer after answering a bunch of questions about options but I think I still got one for another model. Once it arrived I installed it, went through the procedure to 'program?' it before firing it up. I started it up & it sounded perfect. It then died. I started it again, same thing - it died again after about 2-3 seconds. It did feel like it was on all 6 cyls. though. I figured it was the new (used) ecm. I took it out, put the original back in & it returned to how it was )on 4 cyls). I redid all of the above 1 more time with the same results. I am going to buy one off of eBay & match the numbers exactly. Do you know why it consistently died with the new (used) ecm? Any advice on what I'm doing here? Thank you in advance, Mike

ANSWER: Hi Mike, I believe it is dieing in 2-3 seconds because the vehicle theft security system is not programmed to match up with the body control module, and that behavior is exactly what one would expect were that the case. You said you have the 'alarm'. Does that mean just the door lock alarm system or also do you have the skim key alarm (with the pulge in the key head)? Did the procedure you followed discuss how to co-ordinate the pcm to bcm and to the skim module if you have that, for the type(s) of security system you had to start with? Let me know what it said, and also tell me which 'alarm' set up you have and then I can see what went wrong with the install. The fact that the engine runs better is a good sign, now you have to get the alarm system disarmed and into working order. It might be that the used ecm will not match with your existing system(s) but let us see. Please 'rate' my answer (see below). Thanks, Roland

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QUESTION: Hi Roland, Thank you for the fast reply!

The "alarm" to my knowledge is the standard alarm you activate by clicking lock 2x on the fob? Beyond that I don't know. I've been looking for the reprogramming procedure online & cannot find it (I'm still looking). 'Is' there a sequence of steps to do prior to starting/after installing a PCM? I also did verify the PB to be the same on the new (used) pcm but the sequence # is different. I don't know if that matters. Mike

AnswerEdit

Hi Mike, Is there a bulge in the head of the ignition key? Is there a shiny ring around the ignition switch's lock cylinder? Those are the signs of the additional SKIM security system if you have it. Let me know. Try turning the ignition key;"on-off-on-off-on and leave on" doing that in 5 seconds or less elapsed time. Then watch the odometer window in the instrument cluster to see if the mileage reading change to show any 4-digit numbers preceded by a P. That would be a fault code which may verify why the engine won't run beyond 3 seconds. What is the status of the light on the dash that is related to the security system? Roland