I have a question concerning wiring on my 4L60E transmission that I am hopeful someone can provide an answer to. I have installed the 4L60E transmission in my 69 Cutlass (with LS engine) and have run into question concerning the five wires that are in the transmission's wire harness. These are:
-yellow wire
-purple w/ white strip wire
-pink wire
-2 each light green wires
I'm certain that my question has been brought up before and there are no doubt those of you out there who can provide me with information concerning what wires are actually needed and where they connect to. Thank you in advance to anyone able to help

 

The "LT1Swap.com" site can answer many of your questions. There are also ATSG service guides for the 4L60E that can assist. Pin E on the fat trans connector seems to be the most important for the TCC and the shift solenoids. Pin E, according to my references, supplies full time power to the TCC and those solenoids but waits on the PCM to provide a ground path to enable the actuation of those various solenoids. Grounds are just as important on these vehicles as power wiring and the ATSG has a very good description of what you need to check with your multimeter to ensure good grounding.

Rick

 

You're talking about the range switch that the selector shaft goes through.
It's for reverse lights, neutral safety, sends a park/neutral signal to the pcm that interacts with some tables in the pcm tuning.
Heres a picture I found on google.