Had this code show up and transmission is stuck in limp mode on my GC 02 3.3 sport. I have access to several caravans 02 up to 05. So I am thinking about just getting a TCM since I can probably get one for around $30. My question is do I have to take it to the dealer for programming like I would have to the ECM? I know my van does have a chipped key. I've heard I don't as long as the donor doesn't use a chipped key but I do if it does.

I know before the code and limp mode showed up I went from 16mpg city to 10mpg and the van sometimes felt like I was pulling a boat. But seemed to shift fine otherwise. Could a bad TCM cause this? Anything to check before swapping? I put new speed input/output sensors in last year.

Thanks

 

P0605 is an internal PCM fault. I've read of this associated with limp mode but no fixes were stated. http://www.obd-codes.com/p0605

Note: 02 and 03 used separate PCMs and TCMs. In 04 Chrysler started using a combined PCM-TCM in one box on their minivans.

 

oh so only 02 and 03 will be compatible nothing older? I keep reading about having to have it flashed for pinion factor. Is that only if its a different transmission?

 

Nothing older? Correct. To add to the confusion the PCM/TCM combo is just called the PCM. TCM pinion factor flash? Not sure what the deciding factor is but I would think different size rims would be on the list. It's mainly for speedo accuracy.

 

so if I can find a 02 or 03 with same size rims and doesn't have a chipped key should I be able to just plug it in and go and it with a different vin? Would my BCM or ECM just flash the PCM with my key code(if its even stored in it)? Or will the vin mismatch cause a problem with my van having the chipped key?

 

Well I found a TCM on a 02/03 T&C without a chip in the key for $30. It showed to be a mopar reman that was replaced back in 05 under warranty according to the sticker under the hood and the TCM itself. Anyway I put it on and the code went away and the van seems to be shifting fine. Speedometer seems to be accurate since I used my GPS to compare them. However the van that it came off had different size tires then mine so I don't know about that.

I do know for anyone in the future that is looking to replace it, it doesn't seem to need to be flashed as far as checking to see if it fixes your problem. I wouldn't use a TCM from a chipped vehicle though that could cause problems. Make sure the keys it comes off of is black. If you do I'd make sure a dealer is close by.