My TCC is not engaging. I tested the TCC circuit with a test light. Brake switch tested ok and when I grounded the terminal on the ALDL, test light would go out like it was suppose to. While driving the car at cruising speed in 4th gear, when I ground the ecm through the ALDL, TCC engages and works fine. I tested four ground wires on the ECM and they were fine. Do any of you think I have a bad ECM? Scanner shows TCC OFF while driving except every once in a while, it will show ON and you can feel the TCC start to engage for just a second. It also shows my fourth gear switch off and on while driving even though it is in fourth gear. While sitting at idle in park, the fourth gear switch will cycle on and off.
This is on my 87 GN.
This is on my 87 GN.