GM Service Manual Online
For 1990-2009 cars only

Checks

Causes

ATF temperature sensor

Refer to Diagnostic System Check - Vehicle.

Line pressure solenoid

Refer to Diagnostic System Check - Vehicle.

Throttle position sensor

Refer to Diagnostic System Check - Vehicle.

Throttle angle

Throttle angle out of adjustment. Refer to Symptoms - Engine Controls.

Transmission control module (TCM)

Refer to Diagnostic System Check - Vehicle.

2-4 brake band

Burnt or worn 2-4 brake band

1-2 accumulator

Malfunction of accumulator

Broken or damaged oil pump

Seized or broken pump gears

Control valve spool

Control valve spool error

A/C signal circuit to TCM

Harsh shift with open A/C signal circuit when A/C is requested ON