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Removal Procedure

WARNING: This page is about a different car, the 2008 Chevrolet Malibu. However, it is still accessible from the selected car via links, so may be relevant.
    Fig 1: Identifying Booster Vacuum Hose, Clamp & Intake Manifold
    GM1892160Courtesy of GENERAL MOTORS CORP.
  1. Disconnect the hybrid battery. Refer to Hybrid Battery Service Disconnect/Connect .
  2. Drain the cooling system. Refer to Cooling System Draining and Filling (LAT Static Fill) .
  3. Remove the battery tray. Refer to Battery Tray Replacement (LAT) .
  4. Reposition the power brake booster vacuum hose (2) clamp at the intake manifold.
  5. Remove the power brake booster vacuum hose from the intake manifold.
  6. Remove the power brake booster vacuum hose from the clamp (2) on the generator control module coolant outlet hose.
  7. Reposition the power brake booster vacuum hose out of the way.
    8. Fig 2: Identifying Connector Position Assurance (CPA) Retainers
    GM1891759Courtesy of GENERAL MOTORS CORP.
    CAUTION: To help avoid personal injury, additional precautions must be taken prior to working on the generator control module or the generator starter. After removing the 36V battery cables from the generator battery, remove both engine wiring harness connectors from the generator control module. Wait at least 5 minutes and then remove the generator control module cover. Verify voltage levels at all 36V, 12V, and 3-phase connections, are less than 3 volts using a DMM before proceeding.
  8. Remove the 2 connector position assurance (CPA) retainers (3).
  9. Disconnect the 2 engine wiring harness electrical connectors (2) from the generator control module.
  10. WAIT at least 5 minutes in order to allow the voltage stored in the generator control module to discharge.
    11. Fig 3: View Of Generator Control Module Bracket Reinforcement Bolt & Nuts
    GM1891960Courtesy of GENERAL MOTORS CORP.
  11. Remove the generator control module bracket reinforcement bolt (1) and nuts (2).
  12. Remove the generator control module bracket reinforcement (3).
    13. Fig 4: Locating Generator Control Module Coolant Inlet Hose & Clamp
    GM1891970Courtesy of GENERAL MOTORS CORP.
  13. Reposition the generator control module coolant inlet hose clamp (1) at the generator control module using the J 38185  or equivalent.
  14. Remove the generator control module coolant inlet hose (2) from the generator control module.
    15. Fig 5: View Of Generator Control Module Coolant Outlet Hose
    GM1892174Courtesy of GENERAL MOTORS CORP.
  15. Reposition the generator control module coolant outlet hose clamp (1) at the generator control module using the J 38185  or equivalent.
  16. Remove the generator control module coolant outlet hose (2) from the generator control module.
    17. Fig 6: View Of Generator Control Module Cover & Integral Bolts
    GM1891961Courtesy of GENERAL MOTORS CORP.
  17. Loosen the generator control module cover integral bolts (1) and remove the cover (2).
    18. Fig 7: View Of 36-Volt Cable Positive & Negative Terminals
    GM1891958Courtesy of GENERAL MOTORS CORP.
  18. The generator control module will have to be checked for voltage potential using a voltmeter. First, verify that the voltmeter works:
    1. Set the voltmeter to DC voltage.
    2. Measure the vehicle 12-volt battery voltage.
    3. The meter should read greater than +12 volts DC.
  19. Check the generator control module for voltage potential, in order to ensure that the module has been disabled.
    1. Measure from the 36-volt positive terminal (3) to a known good chassis ground. The voltage should be less than 3 volts.
    2. Measure from the 12-volt positive terminal (2) to a known good chassis ground. The voltage should be less than 3 volts.
    3. Measure from the ground terminal (4) to a known good chassis ground, checking for continuity.
    20. CAUTION: To help avoid personal injury, always treat the 3-phase cable and connectors as if voltage is present and as if the surface of all parts of the cable is hot.
  20. Verify that the generator control module 3-phase cables are disabled.
    1. Measure from each phase 1, 2, and 3 connection (1) to a known good chassis ground. The voltage should be less than 3 volts.
    2. After verifying that there is no voltage present, the generator control module 3-phase cables can now be removed from the generator control module.
    21. Fig 8: View Of 36-Volt Terminal Block & Nuts
    GM1891966Courtesy of GENERAL MOTORS CORP.
  21. Remove the 36-volt terminal block nuts (1) from the generator control module.
  22. Lift up, and reposition the 36-volt terminal block (2), secure the block out of the way. Discard the terminal block seal.
    23. Fig 9: View Of Generator Control Module 3-Phase Cable Terminal Block Nuts & Generator Control Module
    GM1891965Courtesy of GENERAL MOTORS CORP.
  23. Remove the generator control module 3-phase cable terminal block nuts (1) from the generator control module.
  24. Lift up, and reposition the generator control module 3-phase cable terminal block (2), secure the block out of the way. Discard the terminal block seal.
    25. Fig 10: Identifying Connector Position Assurance (CPA) Retainers
    GM1891759Courtesy of GENERAL MOTORS CORP.
  25. Disconnect the engine wiring harness electrical connector (1) from the transaxle auxiliary pump module.
    26. Fig 11: Identifying Generator Control Module Ground Strap, Stud & Nut
    GM1892175Courtesy of GENERAL MOTORS CORP.
  26. Remove the generator control module ground strap nut (1) and strap (2) from the module stud.
    27. Fig 12: View Of Engine Wiring Harness Clips
    GM1892187Courtesy of GENERAL MOTORS CORP.
  27. Remove the engine wiring harness clips (1) from the battery tray bracket studs.
    28. Fig 13: View Of Control Module & Nuts
    GM1892176Courtesy of GENERAL MOTORS CORP.
  28. Remove the generator control module nuts (1).
  29. Remove the generator control module (with bracket) (2) from the vehicle.
    30. Fig 14: View Of Control Module & Bracket
    GM1892177Courtesy of GENERAL MOTORS CORP.
  30. Place the generator control module assembly on a clean work surface.
  31. Remove the generator control module bracket to module bolts (2). Separate the generator control module (1) from the bracket (3).
  32. If replacing the generator control module. remove the transaxle auxiliary pump control module. Refer to Auxiliary Fluid Pump Control Module Replacement .
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