Can anyone tell me where the TCM is located on my 2004 Quest?

[sarahmiller]

My 2004 Nissan Quest starting that problem where it does not go anywhere when you give it gas. Stop the car, turn it off, then restart it and it goes. Anyhow, we were told it was probably the TCM. We found a used one since the dealer wanted over $600. We just need to find out where it is located so we can replace it. We heard it was behind the glovebox. Can anyone help?

[Infinitiguy19]

This would be listed in the service manual: http://Nicoclub.com/FSM.

[sarahmiller]

Thanks, but I'm having trouble opening the file.

[lino]

You'll need Adobe Reader to view the file since it's a PDF file.

Try this link and see if it works:

http://www.nicoclub.com/FSM/qu...t.pdf

If not, here's a picture:



It looks like it's on the passenger side of the dash behind the glove box, but I'm not positive.

[ricebike]

have you did a code scan?

in my 2002 quest i found out that my speedometer and odometer failed...

i downloaded the pdf files and did a "scan without the tester" method menntioned in the transmission section of the service manual

confirmed that it was either my speedometer sensor/ the drive gear / or the wiring to it that's bad & putting my vehicle into "failsafe mode"

i can't go past 50mph because the sensor isn't sending a signal to my tcm/ecu

still have to r and r the sensor (been driving the company vehicle since then)

[Joebafett78]

It's under the triangle glovebox on the driver's side behind the steering column. I have a similar issue, and am trying to figure out how to get the damn glove box off without taking the dash apart

[fugi1]

Hello Does any body ever find out how to remove the triangle glove box? I got the same problem. also does the TCM has to be reprogrammed by Nissan? I got mix answers, same Nissan dealership one tech advised it is just a switch parts no programming need it, another tech advises TMC has to be programmed?
confusing
Thanks

[Quest2004]

Here is a picture of what is under the dash on the drivers side of a 2004 Quest - that might be the TCM in white, but it looks different than what I am seeing on ebay. I'll check under my dash later when I have a light. Unfortunately (stupid me), I didn't pay close attention to the underside of the dash when I had it off regarding removal of the dash-top glove box door (not sure if it comes off from the top or bottom). I finally found my pictures and will start posting - I basically had the entire interior of a 2004 Quest removed (not counting all of the goodies under the dash). Directly in the front of the picture is the black plastic defrost vent. To the left are the two connecting plugs going up the A pillar as well as a glimpse of the white (with red stripe) new drain tube for the power roof.

Removing the dash looks imposing (if you need to), but it's not if you are mildly mechanically inclined. I hadn't done one is 30 yrs, but I had the dash off in about an hour if you ever need to do it - it's just a BUNCH of screws. (AND DON'T FORGET TO UNPLUG YOUR BATTERY FIRST UNLESS YOU LIKE THE REMOTE CHANCE OF AN AIRBAG EXPLODING IN YOUR FACE) Your two A pillar plastic covers pop off. The plastic piece over the defroster that runs across the entire width of your windshield (far up front under the windshield - tan or black depending upon your interior color) pops off revealing the screws holding your dash down. The two worst screws are directly under the glass in the far front that you have to use a 90 degree angle phillips screwdriver on. The rest are screws under and around the passenger side lower and driver's side lower. The hardest part for me was to get the passenger side airbag unplugged up under the dash. Note: The dash is also held on by two nuts that screw on from the back side of the dash and hold the passenger side airbag to the dash frame (accessible from the bottom on the passengers side). You basically have to stand on your head to get these two nuts and the airbag electrical plugs popped off.

Note: On mine (2004), to ensure the dash would clear the steering wheel, I had to remove two things:

- two nuts holding the steering column in place under the dash. Do NOT be intimidated by these - they are right there in plain sight under the dash. This allows the steering column to drop down 4-6 inches and give you more clearance.
- The gear shifter. I removed those four bolts and lifted it out, over towards the drivers door, and down - also 4-6 inches.

By temporarily moving these two things, the curved part of the dash around and below the steering column would clear both going out AND going back in. I did the job by myself, but the positioning of the dash (both in and out) would be easier if you had one person helping.

[fugi1]

Quest2004: thank you for the info, now do you know if the TCM needs to be reprogrammed by Nissan or not?

[Quest2004]

I was told it DID have to be, but I also got conflicting stories. I received two "it did's" and one "it didn't" from the three shops i called. I have a friend over at Aamco I can call for a final verdict.

[Quest2004]

Time out. While I in no way am questioning the thought that your TCM could be defective, these are not typical failure items on these vans. Those symptoms described can also be caused by either one or two bad camshaft sensors - there are numerous references to this type of failure on the web. The front one is easy (5-10 minutes), while the back one might take 20-30 minutes. Check to see if you are throwing codes. You can do both sensors yourself for about $230-250 all in (dealer sensors, not after market). There are a couple of tutorials on Youtube that show how to do it.

[fugi1]

I did replace the camshaft sensors and crank sensor. I took it to the Nissan dealership where it was confirmed the TCM failure (according to their computer test) but at the same dealership I was told conflicting information about the reprograming part. I 'll wait on your confirmation. Thanks.

[Quest2004]

Ahh...nevermiiiiind.

..waiting for a callback now..

[Quest2004]

OK..he says it is a crapshoot. IF the TCM is from the same year (assuming a used TCM) and IF it is (obviously) the correct one (for a 4 speed vs. 5 speed auto trans), he has plugged them in they were OK right out of the box. He suspects the dealer is being cautious and covering themselves. For a new one, he said it is almost a moot question as they will probably have a full diag computer hooked up to the car anyway while they are doing the install to see any codes - there is programming involved for a new TCM.

He said these transmissions - if they have a problem.. which is rare - usually have valve body issues. He only remembers one having a TCM issue - most of the others were valve body related. He stated they are rock-solid transmissions that are easy to get parts for when an odd event happens - not at all like the European trans nightmare stories...(which I have experienced first hand)..

[fugi1]

Quest2004, thank your for the information.
There is a newer TCM with a supersede number, I think once Nissan new about the problem, a new version was produced to correct the failure flow.
I am going to get one from ebay with the newer version (which is the same as the one the dealership wants to replace it with) although the one from ebay will be used.
Regarding the transmission, it works fine, only when the TCM gets wacky, the transmission gets stuck in 3rd gear, but if turning the engine off and then right back on, it works normal again.
once again thank you

[Quest2004]

I'll look up there tonight to see if I can visually ID the TCM. It will be a h*ll of a lot easier if you do NOT have to pull that dash.

[Quest2004]

OK, I found it in one of my hardcopy photos - I'll post it tomorrow. Mine is the five-speed version (31036 CK700) and is located on the passenger side under the dash up behind the glovebox directly to the right of the airbag mounting plate (up and to the right of the BOSE amp). You might be able to get at it by pulling the right lower glove box assembly off - hard to tell (five screws if memory serves - two on top and three on bottom). It is mounted vertically up flat against the internal dash components with the plugs on the bottom (silver box). Seeing the plugs on the bottom lead me to believe they intend for you to be able to pull it from the bottom without pulling the dash. One mounting screw is to the left and one is on the bottom - no WAY that is a coincidence...

[Quest2004]

..and this..would be the TCM module. That is one of the airbag brackets (passenger side) on the left and the A Pillar on the right. The new moonroof drain hose is to the right (the way it should have been in the first place). It looks easy to get at with the dash off - still not sure how accessible it is with the dash still on..

[Quest2004]

...and with all due respect Nissan, you mean to tell me you couldn't find ANY PLACE in the interior of this car to install the ECM instead of dropping it in the engine compartment under the front cowling exposed to weather? Who in the h*** thought THAT was a good idea? A second year engineering student would have seen that that was a dumb idea in about ten seconds..especially in the northern states..