This video is part four of a seven part series on the GM 8L90 transmission. In this video, I cover the electronic operation of this impressive transmission. Watch the video to learn about solenoid operation, TCM, PUN and TUN programming, scan tool data and output controls, shfit adapts, temp, mode switch and speed sensor operation and testing.

Here are the other videos in this series:

8L90 Overhaul - part one covers disassembly:    • General Motors 8l90 Overhaul Part One...  
8L90 Overhaul - part two covers assembly, including clutch and gearset assembly and measurements:    • General Motors 8l90 Overhaul Part Two...  
8L90 Overhaul - part three covers valve body:    • General Motors 8L90 mechanical operat...  

8L90 Mechanical and powerflow:    • General Motors 8L90 mechanical operat...  
8L90 Hydraulic theory and operation:
8L90 Torque Converter:    • General Motors 8L90 torque converter ...  
8L90 Rebuilding Particulars:
8L90 Modifications and Tuning:

Special thanks to Precision International, TransGo, and Sonnax for providing me with product to use in these videos. Also thanks to KB Cores and AA Midwest for providing me with a few 8L90 cores at a good price!