Transmission Control Module location

dmax74 · Post by **dmax74** » 19 Jan 2013, 19:48

I have a couple of questions about the TCM. First, where is it located? Second, would this cause the sunroof and interior lights to be inoperable? For the past year or so I have had the Brake Failure Stop ASAP, STC, and SRS lights coming on intermittently ever since the o-rings in my heater core went bad and started leaking. Replaced the o-rings last year with ones I got from Harbor Freight. Well they went out again 2 weeks ago. Last night while driving home I lost my dash gauges except the fuel gauge and the transmission started acting up. Surging like it wanted to die. Pulled over, turned off the car and restarted. Transmission went into Drive but indicator light showed it in Park. Turned off and on again until it went into Drive and the indicator light showed it in Drive as well. Made it home from a 69 mile drive and it ran fine until going up a hill. AS soon as it would downshift I lost all power.
I have been reading alot of post and it appears that the Service light issue is pretty common. Today I went out and replaced the heater core o-rings with OEM ones (didn't realize that anti-freeze would eat through normal o-rings, live and learn). I also removed the CEM and checked all of the connections, soldered all of the green and white splice joints that I could find. Wasn't many, and put it all back together. Disconnected battery(before removing CEM) for an hour or so, reconnected after work was done. What I had done seemed to fix all of the Service light issue that I had before. Now I am getting a Transmission Service on the DIM and my sunroof and interior lights do not work. I understand that everything is on a network but what would cause this? Would a faulty signal to the TCM do it? Also I noticed a purple wire that had splice joints. Any idea what that wire is for? I am 3 hrs from the nearest Volvo dealership here in Central Washington so thats not an option right now. Any help would be appreciated.

Post by **boosted5cyl** » 21 Jan 2013, 09:21

Only skimmed your post, hopefully will get time to read fully later.. TCM is in same place as CEM