About a month ago my wife's 2006 Grand Cherokee Laredo v6, 3.7L, RWD decided to go haywire. It will not shift out of 1st gear (limp mode) even after several restarts. Check engine light, ESP/BAS, and Traction Control lights are all on. Dealership checked it out and said that it needed a new TCM. I was told that the TCM was part of the PCM in my model and year. Bought new PCM (programmed and updated) and installed it, still same exact problems as above. The two codes it is spitting out are p0605 and u0101. Guess my first question would be is the TCM and PCM the same part for my make and model (I've heard yes and no) and does anybody have any other suggestions? Any help is greatly appreciated. Thanks
New member, TCM issues Please HELP
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Thanks for the reply. I guess I'm having a hard time locating my TCM them. I've been told its under the steering column to the right but still can't locate it. Anybody have a good picture of the TCM from a 2006 Grand Cherokee so I know what I'm looking for?
The 3.7 uses the NAG1 transmission. The TCM is a separate item from the PCM. Don't know where it is on the WK, but on my Hemi LX, with the NAG1, it's under the dash by the steering column. Did you keep the original PCM? If so, you can either keep it as a spare, or try to sell it on Ebay or on one of these forums. Be aware that the U0101 code means communication has been lost to the TCM. First thing to do is to find it and check all the connections to it. I'd unplug, inspect, clean and reinstall. Disconnect the battery before you do this though. One other lesson probably learned here is to not to take it to the dealer, except as a last resort.....especially if it's not under warranty. IMO, come to the forums first. So many dealers are just parts replacers and don't really know these vehicles as well as the folks that drive and repair them without dealer help. I know that every time I've reluctantly (and rarely) taken mine to the dealer, I've had to tell them what to do. Good luck, and let us know what you come up with.
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Sorry, no pictures, but it is indeed on the dash panel, under the silencer pad, just to the right of the steering column.
On the silencer pad, there should be cut lines that allow you to cut out that part of the pad that is directly over the TCM.
One you get at it, you can remove the TCM from the bracket and disconnect the wiring harness connectors.
That's it, it should come out once the wiring is removed.
On the silencer pad, there should be cut lines that allow you to cut out that part of the pad that is directly over the TCM.
One you get at it, you can remove the TCM from the bracket and disconnect the wiring harness connectors.
That's it, it should come out once the wiring is removed.
Wow. Thanks guys for all your help. I finally found it and got it removed. Ridiculous placement. Now I'm realizing its not an easy part to find a replacement for either. I did happen to find a TCM for sale taken out of a wrecked WK. Same year, make, model, and engine size except it was 4wd and mine is 2wd. My question is would that make a difference that I'm going from 4wd to 2wd if everything else is the same? Or is this something I'm going to have to have reprogrammed for my vehicle? Thanks
That's a good one!!! I am not sure, but I would think (without looking it up) that the TCM doesn't have anything to do with whether it's 2 or 4 WD, or know the difference. Maybe someone with more knowledge of any possible interactions could elaborate.
beware using junkyard computers in chrysler products. I can not speak with 100% certainty as its not been something I have seen done or attempted myself. That said, most modules have the VIN written to them and will throw a code for a VIN mismatch. Once the VIN is written to a module there is no erasing it. It would be my personal suggestion that you just have the Dealer perform this repair, BUT I completely understand giving the junkyard part a try... It just may cost you more in the end.
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Can anyone confirm the uk 2008 3.0 crd wk/wh version has a tcm or is it build into pcm.
I assume you're asking about a Grand Cherokee? I just know that in a Jeep Liberty it has two different PCMs (Powertrain Control Modules) that have been coupled with the PowerTech. The JTEC was the older controller and the NGC is the newer controller. The JTEC PCM had three connectors on it and used a separate TCM(Transmission Control Module), while the NGC has four because it integrates the TCM. 2006-2007 Libertys use a hybrid bus system in which the PCM, gas TCM, and ABM (ABS and ESP) use the CAN Bus and everything else uses the PCI Bus. The BCM (Body Control Module) then acts as a bridge between the PCI Bus and CAN Bus.
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