LEMON Manuals: Even more car manuals for everyone
Home >> Hummer >> 2008 >> H2 4D Utility Wagon >> Repair and Diagnosis >> External Pages >> Different car >> Section 361 (Automatic Transmission - 2ML70 - Diagnostic Information And Procedures) >> Diagnostic Information and Procedures >> Line Pressure Check >> Main Fluid Pump

Main Fluid Pump

WARNING: This page is about a different car, the 2011 GMC Yukon, 2011 Chevrolet Tahoe, and 2011 Cadillac Escalade. However, it is still accessible from the selected car via links, so may be relevant.
Fig 1: Testing Auxiliary Fluid Pump
GM1981807Courtesy of GENERAL MOTORS CORP.
    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 Level and Condition Check .
  4. Use the scan tool to inspect for any active or stored diagnostic trouble codes. If there are any DTC's, refer to that DTC table first.
  5. Inspect the manual linkage at the transmission for proper function.
  6. Turn the engine OFF.
    7. WARNING:

    When the transmission is at operating temperatures, take necessary precautions when removing the auxiliary pump pressure test hole plug, to avoid being burned by the catalytic converter.

    NOTE:

    You may need to remove or disconnect components in order to gain access to the transmission line pressure test hole plug.

  7. Remove the line pressure test hole plug.
  8. Install J 45056  oil pressure gauge adapter fitting prior to connecting the oil pressure gauge.
  9. Install the J 21867  pressure gauge.
  10. Access the Scan Tool Transmission Output Controls for the Line PC Solenoid.
  11. Start the engine.
    12. 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. Also if you do not have the hood open the engine may go in to AutoStop.

    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 your pressure readings on the scan tool to those indicated on the J 21867  pressure gauge.
  15. If the pressure readings vary greatly, refer to Main Fluid Pump Pressure High or Low .
  16. Turn the engine OFF.
  17. Disconnect the J 21867  pressure gauge and remove the J 45056  oil pressure gauge adapter fitting.
    18. CAUTION:

    Refer to Fastener Caution .

  18. Install the line pressure test hole plug. Tighten the pressure plug to 11 N.m (97 lb in).
scientia non olet · About LEMON Manuals