: Tranny light fixed...FINALLY!!



passionaterage
12-10-07, 07:55 PM
Hey guys. I wanted to let everyone know about my tranny light ordeal. I've posted a couple of threads on here about the problem. Basically, a few months ago my tranny malfunction light started coming on if I drove like 25 or more miles, and it would go into "limp-home" mode. I tried changing a couple of things, but nothing helped. I was afraid this would finally be my Cat killer. I decided to change my Transmission Control Module, I figured it couldn't hurt. So a couple of weeks ago I got a used one on ebay for 50 bucks, and this past Saturday I put it in. And wow, what a change! I guess I didn't realize before that my tranny wasn't changing so smoothly, plus it always had like a little hesitation when going into overdrive. With the new (used) tcm in, it changes perfectly now, you can barely feel it change at all! I was pleasantly shocked! I've driven over 180 miles on it since I put it in, and it's shifting beautifully, and NO tranny light! Sorry this is so long, but I wanted to post this for all the others who may have the "tranny light" problem. It can't hurt to try putting a used, pretty cheap one in and just seeing if it helps. I'm sure glad I did!!

frank moran
12-10-07, 09:39 PM
thanks, this is good information.

Cadi Cat
12-11-07, 01:45 AM
Hey guys. I wanted to let everyone know about my tranny light ordeal. I've posted a couple of threads on here about the problem. Basically, a few months ago my tranny malfunction light started coming on if I drove like 25 or more miles, and it would go into "limp-home" mode. I tried changing a couple of things, but nothing helped. I was afraid this would finally be my Cat killer. I decided to change my Transmission Control Module, I figured it couldn't hurt. So a couple of weeks ago I got a used one on ebay for 50 bucks, and this past Saturday I put it in. And wow, what a change! I guess I didn't realize before that my tranny wasn't changing so smoothly, plus it always had like a little hesitation when going into overdrive. With the new (used) tcm in, it changes perfectly now, you can barely feel it change at all! I was pleasantly shocked! I've driven over 180 miles on it since I put it in, and it's shifting beautifully, and NO tranny light! Sorry this is so long, but I wanted to post this for all the others who may have the "tranny light" problem. It can't hurt to try putting a used, pretty cheap one in and just seeing if it helps. I'm sure glad I did!!

Is this easy to get to, because mine goes into limp mode also but very rarely. And I've just been limping along for about 80k miles or so now, haha.

passionaterage
12-11-07, 03:32 PM
It is pretty easy to get to. It took me about 45 minutes. All you do is take out the glove box (3 allen screws in the top, and I think 2 philips head srews at the bottom. The TCM is on the passenger side firewall right behind it. You just pull it loose from the bracket, unplug it, and put in the new one. Just be sure if you get one on ebay that you make sure it's the right one. Be sure there's a picture of it that shows the part number, or have them send the GM part number before you buy. All years are NOT the same. But once you have the correct one, a very simple job.

Cadi Cat
12-12-07, 10:52 PM
Thanks, sounds pretty simple. I knew it had to be an electronic problem. I feel bad for all the others that got suckered into replacing the tranny all together and then that not solving the problem.

jebfrank
12-18-07, 01:59 AM
Good info, Mines went into limp mode before. Turned out to be a faulty Coolant Temp Switch. The switch went bad, in return keep my engine idle up "trying to get the car to warm up", which in return put a strain on the trans and triggered the light.

smcrosby
12-23-07, 08:33 PM
These weirdo Cat's!!!

Cadi Cat
02-18-08, 01:01 PM
It is pretty easy to get to. It took me about 45 minutes. All you do is take out the glove box (3 allen screws in the top, and I think 2 philips head srews at the bottom. The TCM is on the passenger side firewall right behind it. You just pull it loose from the bracket, unplug it, and put in the new one. Just be sure if you get one on ebay that you make sure it's the right one. Be sure there's a picture of it that shows the part number, or have them send the GM part number before you buy. All years are NOT the same. But once you have the correct one, a very simple job.

I just installed a tcm today and I get the same symptoms. Although the tranny shifts much smoother. Is there anything else that may be causing it to go into limp mode? It rarely does this but it's annoying when it happens and I'd like to get it fixed. I thought I read through the forums about a connector on the transmission itself that may need cleaning that helped someone who was having the same problems. Any tips would be great. Thanks!

PEETYZ
02-18-08, 01:27 PM
There is some electrical connection/s on transmission check and clean those and reset computer take neg bat cable off for 3 mins then replace. also check fluid level and age of fluid I even added a bottle of Lucas transmission fix to renew the bands and lubricate the valves. Best of luck

elvin315
02-18-08, 02:38 PM
I thought it might be a good time to repost this:

http://www.cadillacforums.com/forums/cadillac-catera-cimarron-forum/125997-gm-4l30-e-superior-shift-correction.html

Elvin

passionaterage
02-18-08, 07:54 PM
Well since my old post has been revived, I thought I should give you guys an update. I'd driven for over 800 miles since I put in the new (used) tcm, and thought all was fixed. Well about 2 weeks ago I was driving in stop and go traffic in the city, and the light came on again!! I was so bummed. The tranny still changes as smooth as it did when I first changed the tcm, but I don't know. I'm giving up on this problem. I did come home and put an external transmission cooler on it the next day. Haven't driven it much since then tho, but I'm not hopeful anymore. It will probably just become my "local" car now. It's beat me.

Cadi Cat
02-18-08, 11:38 PM
Well since my old post has been revived, I thought I should give you guys an update. I'd driven for over 800 miles since I put in the new (used) tcm, and thought all was fixed. Well about 2 weeks ago I was driving in stop and go traffic in the city, and the light came on again!! I was so bummed. The tranny still changes as smooth as it did when I first changed the tcm, but I don't know. I'm giving up on this problem. I did come home and put an external transmission cooler on it the next day. Haven't driven it much since then tho, but I'm not hopeful anymore. It will probably just become my "local" car now. It's beat me.

You shouldn't have to make it your local car. It'll still go. You'll just have to power the car off and on again or shift it manually. I make round trips from MI to AL every summer. The light came on once as I was getting on the highway. I cruised it in limp mode through a whole tank of gas and just reset it when I had to fill up. At least mine doesn't ever leave me stranded. It's just annoying sometimes! Especially in heavy traffic when jack rabbit turn arounds and starts are almost a must. My car has been like this ever since I bought it. It's a stupid electrical glitch. My tranny itself is fine. I just wish I could fine the culprit.