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2005 T&C 3.3L, No Start. Possible PCM Fail. Advice?

5K views 66 replies 12 participants last post by  123zorn 
ASD
If Auto Shut Down relay is not turning and staying on, it's ether Immobilizer or PCM...

Make sure ignition switch is working.

Good luck, this is a hands on troubleshooting case (too many variables to do it on a forum)
 
Not true loss of crank position sensor signal will prevent ASD relay staying on and that has nothing to do with PCM issues or SKIM issues
For the sake of "not the sharpest tool in the shed" (or one acting like it) let me add this explanation:

PCM must activate and keep ASD relay ON when the key is turned to ON (RUN) position (before starting the engine).
If it does not (energize ASD and keep ASD relay energized) , you have a problem with Immobilizer (aka SKIS) or PCM related power, ground, or data (PCI bus) circuit.

Once you've verified Immobilizer is not preventing engine from starting, you can go on to troubleshooting no crank condition...

Since OP has no Instrument Cluster functionality (no bulb check or Security LED functionality) the only way to check for Immob "kicking in" without DRB-III equiv. scan tool is to test ASD.

VTSS = Vehicle Theft Security System.
Even though the acronym predates SKIS (Sentry Key Immobilizer System), it's an overarching acronym that can still refer to the the overall / generic "Theft Security System" (aka ignition interrupt and/or alarm functionality)
Originally in UK, VTSS had a special module (IIRC Thacham (sic?) Alarm Module. In America, it was just 'added' BCM functionality / programming.
In any case the argument is pointless, if not childish.
 
Y’all are giving me a headache with all those letters🤣🤣🤣

seriously though,,,how would I go about checking to see if the security thing that causes problems is activated in my 2019 van?
You're SOL, all 5th gen vans have Immobilizer and won't run without WIN? module.. you can't even add a key without scan tool.
go ahead, pull your build sheet
 
OK, atoman, should I check to see if the ASD relay is energized when the ignition key is in the start position?
In RUN (aka ON) position, START is "crank" and ASD should still be on in that position... EDIT: ASD won't be on in start pos. until engine cranks over.

You might want to pull the IPM apart and check for corrosion in connectors and wiring underneath, especially if you're in the "rust belt".

For PCI bus info, look here
 
Its only on for 1 second,, then the ASD shuts off until and rpm over 50 is detected and there are valid crankshaft position sensor signals
Then you can only check for the 1 second "prime" - since starter is disabled, it's not getting sensor signal..
START position won't help
 
Does anybody have any input?
You can't just stick a used pcm from a junk yard (unless donor van had NO Immob).
The module from supplier should have been in SKIM "unlearned" state, so when you plug it in your van it detects a SKIM module and "self-learns" the valid key handshake (and becomes locked to the SKIM & paired key).

If / when you get scan tool, you should check the VIN in PCM - if it matches your van, it should be good / if not, the module you got was not programmed correctly...
 
Nothing disturbing about it.
If you disconnect SKIM, you will have no Immobilizer but you also wont have RKE or TPMS...

It sure seems your problem is between SKIM and transponder keys, maybe skim is not recognizing the keys, maybe someone changed out the skim and didn't pair it with the keys, etc...

Normally, PCM will learn SKIS and will work with the paired keys, in your case it's learning SKIS but not getting a valid key message.

If your goal is to get rid of the Immobilizer, then yes, you should be disconnecting the SKIM.
 
I just read a few of your old posts irrelevant to this thread. You sure know a lot about Chrysler vans. Did you learn all this just from owning these vehicles? Or did you work in a related field?
You'd be amazed how much you can learn when you find the source of the problem... been working on vehicles a while, owning them only "educates" your wallet :)
 
had a hard time installing the PCM because the connections wouldn't go together at first. I suspect someone may have inverted the colored plastic pieces (that go between the PCM and the connectors), but I think I have them in properly now.
If you're saying connector didn't seat easily and fully that is likely the root of your problem, there's probably damage to connector and/or wiring.
Just because you got connector to fit, doesn't mean all the pins are making good contact. (but I can't see what's going on)

Regardless of SKIM, your scan tool should be able to communicate with PCM when ignition is ON (in run pos.) - if it does not solve for what's causing no comm.
 
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