How to flash VIN to used PCM?

Why don't you start by going to the dealer, telling him your story, and asking him about it?

Did you save the old PCM? Maybe if it has a socketed rom chip you can just take the rom from the old one and put it in the new one.

Frankly, I cannot imagine the smog check is going to care. They use the VIN number to determine engine size and such, and since your PCM came out of a GC that presumably had the same engine, when they key either VIN into the test computer, it's going to setup the test computer with the same testing levels.

Ted

I asked for an appointment online, and filled in the details on the online form. I'm waiting for them to get back to me. While I'm waiting, I thought I'd find out what I could. I did find a procedure online for initializing a new PCM. If there's not a VIN number, the DRB III tool prompts you to enter one.

I saved it, but the circuit board is down in a cast housing and under an inch of tough rubbery potting compound. I'm an electronic tech and might have been able to fix it myself if it weren't for that. These use surface mount flash memory chips, not old fashioned socketed ROM's.

Heh heh! Part of the price of living in paradise. In California it's all done by computer. The smog results are uploaded directly to the DMV, using the VIN number is retrieved from the vehicle's computer. I believe they do that to prevent fraud. Normally it's very slick. This is just an oddball case. I may have to buy another PCM if I can't get the proper VIN programmed into this used one.

-Paul

I would still talk to the smog people, they must have a way to override the VIN that is pulled from the vehicles computer.

Legally I do not think that there is any standing for a government agency to use a VIN pulled from a vehicle computer as the authoratative VIN. I suspect that buried in some federal law is a statement that says that the VIN displayed in the winshield is the only legal authoratative VIN. There's certainly federal law that requires the VIN to be unique, and for it to be displayed in a particular location. It would seem to me that if you have a running vehicle that otherwise passes smog, that CA cannot legally compel you to make a VIN that is pulled from the vehicle computer match the actual VIN assigned to the plate riveted to the chassis. After all, not all car computers have VINs in them, and I do not believe that OBD-II requires VIN availability as one of it's parameters. You could try going here and looking into this:

I think that the VIN inclusion in OBD was for the OBD-III standard which is after your 1998 vehicle. I think that CA wanted this so they could eventually design a system that when the car's emissions systems failed that the car would report this to a state agency that could then compel the owner to get it fixed immediately. But this scheme raised a huge controversy and I think it was abandonded.

Ted

Just take the smog test and be on your way, The only thing they want to know is if the engine lite is on and what is coming out the tailpipe. If the PCM was not right for the vehicle the lite would turn on and fail.

Glenn Beasley Chrysler Tech

In the land of unintended consequences and feel-good laws, they would probably require him to scrap the vehicle because the VIN's don't match. Just their contribution to "saving Mother Earth". :)

Bill Putney (To reply by e-mail, replace the last letter of the alphabet in my address with the letter 'x')

Vin no. can not be reset after it is programed in but. But you might check it with a scanner. A used one may not even have had it programed into the pcm yet. If that is the case you can punch it in with a good scanner. Also when you have a scanner on it check and see if the tire size is set right. That part can be reset. The Vin No. in pcm should not be a problem on inspection as long as check engine light is not on and no codes set. Good Luck MT

That's encouraging, I guess I can ask. I'm dubious, though, unless the smog techs have a way to override the VIN. As I said, it isn't going to fly if they try to send the pass data to the state with the wrong VIN number.

-Paul

This is annoying, but I support the smog program. It's really necessary in California. Even with these laws, my eyes sting from the smog when I visit relatives near Los Angeles.

So I guess you could say they are literally "feel-good" laws. ;-)

-Paul

Are you sure the DMV/inspection station reads the VIN from the car? I don't believe there are any generic protocols to permit this, so they would need specialized equipment for all makes, which doesn't sound realistic.

Where I live, the emissions inspection station is also online in real time to the DMV. The VIN is obtained by scanning the barcode inside the driver's door. For some reason the computer always prompts for the engine model, even after it already has the VIN (which could be decoded for the engine model if they felt like it). The inspection is primarily now done via the OBD-II system, in most cases they don't even do a dynanometer test for OBD-II cars, which they had been doing earlier.

My inspection station is friendly so I've been able to watch the process pretty carefully.

I believe you are correct about VIN not being in the OBD-II parameters. That level of detail generally requires specialized equipment from a dealer (or Snap-On, etc. --very expensive) There is no OBD-III standard active. The newer CAN protocol will be required by all vehicles, I think by M.Y. 2008. Many cars have been already using it, and started as early as 2003.

Talk to the inspection station and explain the situation. And If all else fails. A computer rebuilding co. should be able to erase the vin no. Or exchange you for another one. Check you local area for one. I have one in Texas if you need there 800 no or address. Post back Good Luck

OK, got it smogged so here's the scoop: They just scanned the barcode on my registration renewal form which the state (California) sent. They got the VIN number off of that form, not from the PCM. So the junkyard PCM wasn't an issue, just as some of you said. I worried about it for nothing. ;-)

It passed smog with flying colors, so I'm set. BTW, I paid $65 + $15 shipping for that used PCM. I found it up in Washington using this website:

Thanks for your help, guys.

-Paul

You are welcome and. Thanks for posting back how it went. Glad all went well with no problems. I really do not know why they put the vin no. in the pcm anyway. It does nothing as far as the pcm goes.:grinyes: :grinno: :lol: MT