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mygalantwasfree
02-21-2011, 10:42 PM
So I just found out today that my OBD-II scanner doesn't actually read transmission codes. I followed the instructions given at this webpage to pull my TCU code:
http://www.plymouthlaser.com/tcucodes.htm

(I have a piece of crap auto trans that was rebuilt at 100k just FYI)

I got two "long" pulses and one "short" pulse, which I think means
code 21: Open-Circuited Kickdown Servo.
I have been driving this car 20k miles with this error code in the transmission and I didn't even know it.
Does anyone know any specifics about what this servo does?

The wire leading to the kickdown servo switch was shredded and frayed at the plastic connector. I don't think it's been connected since I got the car. I pulled out the servo switch and soldered a wire onto it. I'll splice this into the harness where the connector used to be.
I am very optimistic about this code. :orangecool: I'm hoping it will cure my harsh 1-2 upshifts. I'm also hoping that it will allow the transmission to move into a higher gear after cresting long hills. As of now, the tranny "hangs" in a lower gear with the engine racing when I crest a hill. It's like the transmission forgets that it needs to upshift. I can fix this issue while driving by bumping into neutral and then back into drive again.

Any ideas?

mygalantwasfree
03-01-2011, 03:12 PM
Update: I repaired the broken wire connector by the servo. I now have the sensor working again, but unfortunately I did not detect any discernible difference in shifting behavior.