GM Service Manual Online
For 1990-2009 cars only

Object Number: 1897993  Size: SH

Special Tools

EN 21867 Pressure Gage

For equivalent regional tools, refer to Special Tools.

    Warning: Keep the brakes applied at all times in order to prevent unexpected vehicle motion. Personal injury may result if the vehicle moves unexpectedly.

  1. Install a scan tool.
  2. Start the engine.
  3. Inspect the transmission for the proper fluid level. Refer to Transmission Fluid Check.
  4. Use the scan tool to inspect for any active or stored diagnostic trouble codes.
  5. Inspect the manual linkage at the transmission for proper function.
  6. Turn the engine OFF.
  7. Remove the line pressure test hole plug.
  8. Install the EN 21867 Pressure Gage .
  9. Access the Scan Tool Transmission Output Controls for the Line PC Solenoid.
  10. Start the engine.
  11. Note: 

       • In order to achieve accurate line pressure readings, the following procedure must be performed at least 3 times in order to gather uniform pressure readings.
       • The scan tool is only able to control the line PC solenoid in PARK and NEUTRAL with engine speeds below 1500 RPM. This protects the clutches from extreme high or low line pressures.

  12. Use the scan tool to increase and decrease the Line PC Solenoid in increments of approximately 100 KPa (15 psi). The scan tool commands the increment values automatically.
  13. Allow the pressure to stabilize between increments.
  14. Compare the pressure readings on the scan tool to those indicated on the EN 21867 Pressure Gage .
  15. If the pressure readings vary greatly, refer to Fluid Pressure High or Low.
  16. Turn the engine OFF.
  17. Remove the EN 21867 Pressure Gage .
  18. Caution: Refer to Fastener Caution in the Preface section.

  19. Install the line pressure test hole plug. Tighten the pressure test hole plug to 12 N·m (106 lb in).