Electrical Problem with 93 4L60E???
Thread Starter
Staging Lane
Joined: Jun 2009
Posts: 58
Likes: 0
Electrical Problem with 93 4L60E??? had a buddy hook this truck up to his snap on diagnostic computer to try and figure out the problem and this is what its doing, reverse worls fine, when placed into drive, the transmission starts out in second gear(you can tell and the computer also verified that it was starting out in second, regardless of speed, it will not shift out of second into third... when placed into manual 1st, it starts out in 1st, then you can manually shift into second, but again regardless of speed,( i took it to 55) it will not shift out of second into third. he asssumed it may be in limp mode but i know pulling the fuse for the tranny will put it in limp mode so i did that to check and the transmission acted totally different , it was taking off in third gear then. put fuse back in and it went back to what it was doing before... this is a rebuilt transmission by a pretty reputable guy around here so im having a hard time doubting his work, however, is it possible that the wires in the pan that go to the solenoids where crossed and hooked up to the wrong solenoids? any help is greatly appreciated
Thread Starter
Staging Lane
Joined: Jun 2009
Posts: 58
Likes: 0
Well the guy gave me a 120 day warranty on it butfor
some reason or another, I had speedometer problems as Soon as I put the trans in, turned out to be a bad conection where my gauge cluster plugged in, we found that our after the warranty had already expired. I will have to get the truck hooked back up to that computer to see what codes were thrown and il post back tomorrow hopefully
some reason or another, I had speedometer problems as Soon as I put the trans in, turned out to be a bad conection where my gauge cluster plugged in, we found that our after the warranty had already expired. I will have to get the truck hooked back up to that computer to see what codes were thrown and il post back tomorrow hopefully
No, it would have had this problem when you drove it home from the trans shop if the wires where crossed up. It would have done this on the first drive.
Trending Topics
Old trans worked fine but wore out, new trans doesn't work fine. No changes except for the transmission?
It's in the transmission.
LS1 Tech Stories
The Best V8 Stories One Small Block at Time
6 Common C5 Corvette Failures and What's Involved In Repairing Them
Pouria Savadkouei
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph
Verdad Gallardo
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked
Pouria Savadkouei
Top 10 Most Powerful Chevy Trucks Ever Made!
Hennessey's New Supercharged Silverado ZR2 Has 700 HP
Verdad Gallardo
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes
Verdad Gallardo
Awesome K5 Blazer Restomod Comes With C7 Corvette Power
Verdad Gallardo
10 Camaros You Should Never Buy
10 LS Engine Myths That Refuse to Die
Verdad Gallardo Looks like a year long problem, interesting stuff. Good luck.
Posted a year ago VVVV
Posted a year ago VVVV
well heres an update after pulling the tranny out and watching the guy go through it again and getting the truck put back together.
pulled it out and replaced all the the electronic components inside the transmission, put the truck back together and guess what...STILL doing the same thing. we hooked the truck up to the scanner before and after pulling it back out and the scanner (not the cheap little code reader from auto zone) said it was the 2-3 shift solenoid...well like i said it still through the same code even after i replaced everything electrical inside the trans...
i started looking through the wiring harness and found a couple places where it had been cut a saudered back together and even in some places just wires cut and stripped then twisted back together ...couldnt believe it ...so went ahead and yanked the under dash and engine wiring harness out and it was a pretty big mess....now here is the question, could the wiring be causing this or is it the computer?...ahhhh
pulled it out and replaced all the the electronic components inside the transmission, put the truck back together and guess what...STILL doing the same thing. we hooked the truck up to the scanner before and after pulling it back out and the scanner (not the cheap little code reader from auto zone) said it was the 2-3 shift solenoid...well like i said it still through the same code even after i replaced everything electrical inside the trans...
i started looking through the wiring harness and found a couple places where it had been cut a saudered back together and even in some places just wires cut and stripped then twisted back together ...couldnt believe it ...so went ahead and yanked the under dash and engine wiring harness out and it was a pretty big mess....now here is the question, could the wiring be causing this or is it the computer?...ahhhh
Thread Starter
Staging Lane
Joined: Jun 2009
Posts: 58
Likes: 0
i have since then replaced every bit of wiring in the truck and the problem before was with a different transmission that i junked, turns out that transmission was a 95' model with the PWM type pump. This transmission is definatley not PWM
Theres a plate on the PCM held on with two screws. Take that off and you see the PROM, it has a blue plastic cover on it. The chip is in this part.
The code is removed from this one.
The code is removed from this one.
Last edited by Jays_SSZ28; Dec 22, 2017 at 09:53 PM.
Thread Starter
Staging Lane
Joined: Jun 2009
Posts: 58
Likes: 0
The numbers I gave you were the numers on the blue plastic covers . There are two sets of 4 digit delco #s on a silver sticker inside that read "4895,3177" on the first one, th second is hard to read but I believe they are "1478,3056"
And another problem is, even if you bought a new pcm they expect you to use your old PROM.
If I were you, and I've done this myself, I'd find a pick your part junkyard and pull the pcm out of a truck of the same year with the same engine and transmission, and the same service number. The pinouts are not the same between certain different pcm service numbers. This could be the problem when you pulled a wiring harness out of a different truck, you might have the right pcm for your truck with the wiring harness thats pinned different.
Reading the 30+ posts you've put up in the past year about this same problem, I'd start with another wiring harness with it's matching pcm out of a truck exactly like yours.
I've learned that you can't trust organized, paranoid warehoused auto salvage companies, they'll hand you whatever they can get to easiest and argue with you that it will work. It's best to pull your own stuff.
Thread Starter
Staging Lane
Joined: Jun 2009
Posts: 58
Likes: 0
Thanks for all your input, it's greatly appreciated.. I pulled the wiring harness tata in the truck now out of a truck in a junkyard, I believe the truck was a 94 gmc 1/2 ton 4x4 with the same engine, is it still possible that the wiring harness is pinned differently? At this point I'm loading te truck up and taking it to a transmission shop that said " they could diagnose it for free" ad going from there