Had this posted on General Tech for a while with NO response.
HOPE someone is up to the challenge here.
2004 Cavalier.
Torque converter won't lock up on it's own. When I have the Tech2 hooked up while on test drive, I can make trany do everything it is supposed to do, including locking in the converter. All shifts, All gears great.
Have replaced solenoids under transmission side cover with no fix.
Currently have jumper wires from BCM to a toggle switch inside the car. With switch ON converter is locked in. With switch OFF, converter locked out.
Driving process now as follows---
Switch OFF around town, then when on highway, up to speed, bump into neutral-shut off engine - flip switch ON - re-start - back in gear and is locked in for the ride. Reverse process when pulling back into town to keep from killing it at the next stop.
A real PAIN in the arss!!
Is it possible that the radio plays a part in computer communications?
Previous owner installed a cheap quality stereo.
The stereo hasn't worked right from about the same time as converter issues showed up.
Could there be a connection????
Would getting an OEM radio possibly help???

Thank you for any advice.

 

any problems with the stop lamp switch or cruise brake switch? These inputs to the pcm will keep the tcc in unlock. check the pid for these switches with the tech2 and make sure they are not causing the pcm to keep the tcc off.


the bcm isn't wired into anything to do with tcc. only the pcm...which answers your radio problem...

 

Thanks Tech2
Cruise works fine and shuts off when pushing brake pedal. Brake lights, turn signals also working fine.
Sorry, I didn't know the difference between BCM & PCM.
We have the jumper wires from the box under the hood on the fire wall.
Guessing now, that's the PCM
Been a while so I don't remember what the code was but it thinks that the tcc solenoid is faulty. If I recall, there were 3 solenoids and we replaced them all while side cover was off. Made no difference.
I regards to the radio--- I understand that in many cars the radio plays an integral part in computer communications. It's like everything will work but computer won't tell it to.
Just shooting in the dark.
Need to replace the stereo anyway. Just haven't got around to it. Daughter's car and she doesn't drive it in the winter.
Thanks