1995 4T60E Electronic Tranny Problem

[big420dog]

I have a 95 LeSabre with the 4T60E transmission. I'm doing tests on the solenoids inside the side case and reference says I should get 20-50 ohms of resistance for each solenoid. I checked each one and I only get 10-12 ohms.... Anyone have any ideas? Could it be an internal short or what?

[BNaylor]

Originally Posted by big420dog

I have a 95 LeSabre with the 4T60E transmission. I'm doing tests on the solenoids inside the side case and reference says I should get 20-50 ohms of resistance for each solenoid. I checked each one and I only get 10-12 ohms.... Anyone have any ideas? Could it be an internal short or what?

What are you referencing to for the resistance values? Are you directly on the respective solenoid with all electrical plugs disconnected? The 10 - 12 ohms seems like a little too low resistance for a solenoid coil such as PCS or TCC. What ever point you are measuring from, this time reference each point to ground. Positive (red) lead to the solenoid contact or pin and the negative (black) lead to engine or battery negative ground. If you get any type of reading referencing to ground then you have a problem such as an internal short. It should read open when checking against ground.

I am not sure what the proper coil resistance values are for your model and year but hope the info helps. Good luck!

[big420dog]

well ALLDATA says that when cold i should get a resistance value of between 20 and 50 ohms at the transaxle connector where it plugs in to the tranny. with all the PCM wires disconnected. and ALLDATA says the PWM and TCC apply solenoid are to be 10-12 ohms and when tested are only 6-7 ohms

[LeBuick]

Originally Posted by big420dog

well ALLDATA says that when cold i should get a resistance value of between 20 and 50 ohms at the transaxle connector where it plugs in to the tranny. with all the PCM wires disconnected. and ALLDATA says the PWM and TCC apply solenoid are to be 10-12 ohms and when tested are only 6-7 ohms

What kind of ohm meter are you using? Is it highly accurate or does it have a good size margin of error? I do electronics and not too knowledgable with cars but with an electronic silinoid, I would put the proper supply voltages on the terminals and see if it actuates (you should hear it). This will only test the coil and not if the silinoid is mechanically working...

[BNaylor]

Originally Posted by LeBuick

What kind of ohm meter are you using? Is it highly accurate or does it have a good size margin of error? I do electronics and not too knowledgable with cars but with an electronic silinoid, I would put the proper supply voltages on the terminals and see if it actuates (you should hear it). This will only test the coil and not if the silinoid is mechanically working...

Hopefully he's using a good digital multimeter. Based on the way he is troubleshooting the solenoids appear to be left intact and still connected underneath the tranny side cover. He is checking at the so called GM 20 electrical way connector. I doubt he will be able to see or hear the specific solenoid activating if a supply voltage is applied while it is still mounted to the tranny inside the side cover assembly unless he has hearing like Superman to include X-ray vision. The 4T60-E and 4T65-E are similar except the 4T60-E has a vacuum modulator. BTDT.

It is not an easy job removing the tranny side cover but can be done.

[big420dog]

well i have removed the side cover before and i have replaced all but one of the solenoids already. but im thinking its the internal wiring because it seems like it only shifts correctly in to 3rd and then OD until it gets warmed up and then only shifts from 1st to 2nd NO 3rd or OD

[BNaylor]

Originally Posted by big420dog

well i have removed the side cover before and i have replaced all but one of the solenoids already. but im thinking its the internal wiring because it seems like it only shifts correctly in to 3rd and then OD until it gets warmed up and then only shifts from 1st to 2nd NO 3rd or OD

Thats a tough one. Which solenoid wasn't replaced? Did you replace the solenoids already swapped out with genuine GM or aftermarket?

Looks like your only choice is to remove the side cover again and visually check the wiring. I'd check each solenoid connector plug to make sure they are seated correctly and going back to the 20 way connector. Plus check the coil resistance on each one for the 20 - 50 ohms with the connector off. You could run continuity checks between each solenoid connector back to the 20 way plug if you know which pin it is connected to in order to determine if it is in fact a wiring problem. Check every signal or plus (+) pin to ground and see if there is a short on that run or leg.

The reason I mentioned GM or aftermarket parts, I helped a friend several months ago troubleshoot his 4T65-E tranny on a '98 Regal GS and we found the TCC solenoid the reason for the torque convertor not locking up. He decided to save some money and bought a Sorensen aftermarket. It worked for about 1K miles and crapped out. We had to do it all over again but this time went with the AC Delco replacement. It has been working since.