On the 4T60E (1996) transmission, what 'should' happen if you disconnect the harness on the front of the transmission (the round plug)? The transmission has been upshifting harshly lately, and from what I thought I had read,I thought that disconnecting the harness would let the transmission go into a 1-2-3 pattern, with maximum pressure, but should operate normally otherwise. I disconnected it to see if it was some sort of electrical problem causing the car to act this way since I've had various electrical problems with it over the years.
Instead of doing what I thought it was supposed to do, the car dropped from 1st to 3rd at about 5 MPH, and stayed there unless the car came to a complete stop, to the point that I went about 200 feet and stopped the car to reconnect the harness before it tore the bottom out of the engine. Did I read the wrong thing about disconnecting the harness? I certainly won't try that again (and I know I'm lucky that I didn't destroy something), but for informational purposes, what would have caused this to happen? I've already got the car scheduled for the shop this week, but they have looked at it already twice and can't tell me what is wrong with it. Perhaps someone knows a good transmission shop in the Raleigh, NC area?
Thanks in advance, Dave