Coolant Leak Testing - Starter/Generator Control Module

2004 Oldsmobile Bravada RWDSECTION Coolant Leak Testing - Starter/Generator Control Module
WARNING: This page is about a different car, the 2004 GMC Sierra, 2004 GMC Cab & Chassis Sierra, 2004 Chevrolet Silverado, and 2004 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.

Tools Required

    CAUTION: To avoid being burned, do not remove the starter/generator control module (SGCM) cap while the SGCM is hot. The cooling system will release scalding fluid and steam under pressure if the SGCM cap is removed while the SGCM is still hot.
  1. Follow the steps below in order to remove the starter/generator control module (SGCM) coolant tank cap.
    1. Slowly rotate the cap counterclockwise.
    2. Stop rotating and allow the hissing to stop.
    3. After all the hissing stops, continue turning counterclockwise in order to remove the cap.
  2. Fig 1: View Of SGCM Coolant Inlet Hose, Coolant Tank & Inlet Hose Clamp
    GM1206674Courtesy of GENERAL MOTORS CORP.
  3. Test the operation of the pressure cap. Refer to Pressure Cap Testing - Starter/Generator Control Module .
  4. Wash the pressure cap mating surface with water.
  5. Use the J 24460-01  with the J 46143  in order to apply pressure to the cooling system.
    IMPORTANT: Do not exceed the pressure cap rating.
  6. The cooling system should hold the rated pressure for at least 2 minutes.

    Observe the gage for any pressure loss.

  7. Repair any leaks as required.
RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • You smell fuel, burning insulation, or see smoke.
  • Brakes feel soft, pull hard to one side, or make grinding noises.
  • The engine overheats, stalls repeatedly, or misfires under load.
  • You are missing required tools, torque specs, or safe lifting equipment.
  • You are not confident in the next step or safety outcome.