Shop says TCU after rebuild

[TymmVonD]

Bought casr with no forward only reverse in January 2012. Had rebuilt the next week. Added Translab kit. Replaced temp sensor a few days later and spilled coolant on tranny. Now fans work. Next day I get a P1750 malfunction solenoid assembly trans code. With less than 100 miles i go back for 1 week checkup. Explain code and that i thought was from getting connections wet with coolant. Inspector agreed, but still throws code after full day of driving. Now 900+/- miles on rebuild. Took back yesterday, kept overnight, tested solenoids=shop says bad tcu. Fuse in TCU was a 30amp, swapped to 10 amp when i got home. Checked connections under dash. Anything else to check?

 

[Bud92gsx]

If the tcu was bad, the car would be stuck in 3rd gear(limp mode).You got some awfully smart mechanics over there.

 

[94allwheeldsm]

Agreed ^, if the TCU was bad it would be in limp mode. If it continues to throw the code try replacing the part for the thrown code.

 

[TymmVonD]

Exactly what i told Bill at ALLPRO transmission Jackson, TN. If TCU was bad would be in limp. So he showed me ALLDATA, which shows "REPLACE TCU" in bold blue. He said he would replace solenoid pack "again", since i was billed for a new solenoid pack. Said some come defective brand new. I read the packs rarely go bad and can last 300k miles. Instead of replacing pack, he had his builder ohm test them. Said were in spec. And the pack isnt under warranty if goes bad. I'm pissed. Have searched forums for days on end. No fingernails left. Soooo stressed. Help me guys. ECU should be fine then. TCU acts as if unplugged.

BTW, car has balls. faster than my little bros GST. Seems fine mostly. Has acted like it didnt know how to shift a couple times. But code shows religiously evry day after reset.

 

[Bud92gsx]

Also if tcu was unplugged it might be in limp mode as well.Pull code replace part,see what happens.

 

[TymmVonD]

Tried to uploads pics. TCU has no burns, no popped or leaking caps. Looks good. ECU is covered in amber crust. Anyone wanna sell a md762042 tcu from a auto/manual swap?

 

[Bud92gsx]

I don't have one or I would sell it to you.Junkyards possibly.Manuals don't have tcu's.

 

[dsmboise]

Exactly what i told Bill at ALLPRO transmission Jackson, TN. If TCU was bad would be in limp. So he showed me ALLDATA, which shows "REPLACE TCU" in bold blue. He said he would replace solenoid pack "again", since i was billed for a new solenoid pack. Said some come defective brand new. I read the packs rarely go bad and can last 300k miles. Instead of replacing pack, he had his builder ohm test them. Said were in spec. And the pack isnt under warranty if goes bad. I'm pissed. Have searched forums for days on end. No fingernails left. Soooo stressed. Help me guys. ECU should be fine then. TCU acts as if unplugged.

BTW, car has balls. faster than my little bros GST. Seems fine mostly. Has acted like it didnt know how to shift a couple times. But code shows religiously evry day after reset.

BTW- ALLDATA is a program by AutoZone, I think, and they would be HAPPY to sell you a R&R TCU, even if you didn't need it.

TCUs are a serious pain. Good Luck, I can't seem to find any.

 

[Firsts tuner]

BTW- ALLDATA is a program by AutoZone, I think, and they would be HAPPY to sell you a R&R TCU, even if you didn't need it.

TCUs are a serious pain. Good Luck, I can't seem to find any.

Alldata is used by most reputable shops. It's an excellent and reliable program. If you need a new tcu pm me and I can set you up with a member that has a few laying around, if you can't find one on the classifieds.

 

[dsmboise]

My mistake. It's ALLDATAdiy that is from AutoZone. I tried using it (paid) on my girlfriend's Subaru. It wasn't much help. I did better taking a common-sense approach to troubleshooting the problem. But, to be fair to ALLDATAdiy, I WAS working on a Subaru!

But, the op trouble is similar to what I am experiencing in my 1G.

I am going to try testing the continuity of the wires leading from the TCU harness to the case connector (solenoids) before I tear back into the case to replace solenoids.

Also, I plan to test the resistance for each solenoid lead coming out of the case connector to trans case, and then to chassis ground. this might help rule out bad connections, including grounds.

Hopefully, that will help you narrow down your problem, unless you have fixed it already.

If you have, will you please share what it was / how you tracked it down?

GOOD LUCK!!

-------------------------------
OK! I fixed mine.

It was just like was said on another thread.

I had the connectors switched up.

I know someone once said to check the color coding on the wires.

That did me no good until I had a pin out diagram from another post. When I find it, I WILL link to it here.

PLEASE try this before buying a TCU. I did NOT and I paid $250 extra dollars for my mistake.

But...I have an excuse...I'M AN IDIOT!!!

OP, PLEASE READ


http://www.dsmtuners.com/forums/articles-drivetrain/277172-1g-tcu-guide.html

 

[justinlehigh]

I have a 92 1G NT AT. I have read the 1G TCU guide and I'm not sure if mine is a typical situation or not.
I had a trans fluid leak a month ago, so my mechanic did a filter and fluid change, cleaned solenoids...also found two bolts that mounts the trans to the block missing. Everything worked great.
Couple weeks later I had the rear main seal changed due to serious oil leak. It was leaking before the trans leak, but waited for my tax money.
After the rear main seal change, it never felt right again. From a dead stop accelerating there was a bad vibration from the trans area up to about 15mph. After that it was smooth and NO rough shifts.
Mechanic looked at it and said I needed a trans mount because it's so old and worn.
Ok, well before I could get it, one day I lost 4th gear. Would shift through to 3rd, then open rev as if in neutral. I made it back to the shop, but now I don't have reverse either, and my mechanic seems stuck on the problem. The check engine light wasn't on at first, but now in his care it is, and it's throwing codes for solenoid issues. He said Friday he was going to take out the solenoids and check them and go from there.
Does this sound like a TCU gone bad,...or a tranny? It was shifting smooth so I don't think it's mechanical, but it just seems too coincedental that this happened right after main seal change.
Please help! I love these forums. You guys have helped me so much... Thanks!