Trouble Shooting

WARNING: This page is about a different car, the 2003 GMC Sierra, 2003 GMC Cab & Chassis Sierra, 2003 Chevrolet Silverado, and 2003 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.

If Fast Learn will not run and the above-stated conditions have been met, ensure the following:

Transmission fluid temperature at 40-100°C.
Closed throttle and engine at warm-idle RPM.
No active DTCs.
All speed sensors are connected and functioning properly.
NSBU switch properly adjusted and functioning.
Main pressure within specification.
TCC slip speed less than 100 RPM at idle in park/neutral.