GM Service Manual Online
For 1990-2009 cars only

Diagnostic Category

Diagnostic Information

The following table consists of eight diagnostic categories that are located in the left-hand column. Using this column, choose the appropriate category based on the operating conditions of the vehicle or transmission. After selecting a category, use the right-hand column to locate the specific symptom diagnostic information.

Fluid Diagnosis

This category contains the following topics:

    â€¢ Fluid condition, such as appearance, contaminants, smell, overheating
    â€¢ Line pressure, high or low
    â€¢ Fluid leaks

 

    â€¢ Refer to Transmission Fluid Check .
    â€¢ Refer to Transmission Overheats .
    â€¢ Refer to Line Pressure Instability .
    â€¢ Refer to Low Line Pressure .
    â€¢ Refer to High Line Pressure .
    â€¢ Refer to Automatic Transmission Fluid Leaks .
    â€¢ Refer to Fluid Leak Diagnosis .

Noise and Vibration Diagnosis

This category contains the following topics:

    â€¢ Noise, drive gear, final drive, whine, growl, rattle, buzz, popping
    â€¢ Vibration

 

    â€¢ Refer to Final Drive Noise or Hum Noise .
    â€¢ Refer to Noisy in Reverse Only .
    â€¢ Refer to Ratcheting Noise .
    â€¢ Refer to Gravel or Grating Noise .
    â€¢ Refer to Moaning Noise .
    â€¢ Refer to Rattle Noise .
    â€¢ Refer to Vibration .
    â€¢ Refer to Flexplate/Torque Converter Vibration Test .
    â€¢ Refer to Noise and Vibration Analysis .

Range Performance Diagnosis

This category contains the following topics:

    â€¢ No Drive/Slips in Drive
    â€¢ No Reverse/Slips in Reverse
    â€¢ No Drive and Reverse
    â€¢ No Park
    â€¢ Stays in Park
    â€¢ Stays in Drive
    â€¢ Stays in Low
    â€¢ Stays in Intermediate
    â€¢ Stays in Reverse
    â€¢ Range Selector Position Inaccurate

 

    â€¢ Refer to No Drive in Forward Ranges .
    â€¢ Refer to Slips in Drive .
    â€¢ Refer to No Reverse .
    â€¢ Refer to Slips in Reverse .
    â€¢ Refer to No Forward and Reverse .
    â€¢ Refer to No Park .
    â€¢ Refer to Transmission Does Not Shift Out of Park .
    â€¢ Refer to Stays in Drive .
    â€¢ Refer to Stays in Low .
    â€¢ Refer to Stays in Intermediate .
    â€¢ Refer to Stays in Reverse .
    â€¢ Refer to Range Selector Displays Incorrect Range .
    â€¢ Refer to DTC P0705 .
    â€¢ Refer to DTC P1756 .
    â€¢ Refer to DTC P1758 .

Shift Quality Feel Diagnosis

This category contains the following topic:

Harsh Garage Shift

 

Refer to Harsh Garage Shift .

Driveability/Ratio Control Diagnosis

This category contains the following topic:

Poor driveability

 

Refer to Poor Driveablity - Poor or No Ratio Control .

Torque Converter Diagnosis

This category contains the following topics:

    â€¢ Torque converter diagnosis
    â€¢ TCC does not apply
    â€¢ TCC does not release
    â€¢ TCC apply/release quality
    â€¢ Poor acceleration/No torque multiplication

 

    â€¢ Refer to Torque Converter Diagnosis .
    â€¢ Refer to Flexplate/Torque Converter Vibration Test .
    â€¢ Refer to Torque Converter Clutch Stuck On .
    â€¢ Refer to Harsh Torque Converter Clutch Apply .
    â€¢ Refer to Torque Converter Clutch Slipping .

Indicator On or Message Center Displays Message

This category contains the following topics:

    â€¢ Message Center displays "Trans Hot"
    â€¢ Message Center displays "Trans Cold"

 

    â€¢ Refer to Transmission Fluid Check .
    â€¢ Refer to Transmission Overheats .
    â€¢ Refer to DTC P0218 .
    â€¢ Refer to Transmission Does Not Shift Out of Park .

Symptom Not Found or No Symptom Detected

    â€¢ Refer to Transmission Fluid Check .
    â€¢ Refer to Road Test .
    â€¢ Refer to Line Pressure Check .