Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
2010 Hummer H3 Base, AutomaticFACTORY OEM SERVICE PROCEDURE
Installation Procedure
- Install the ECM (1) into the ECM mounting bracket, allowing the tabs to fully engage.
- Connect the body wiring harness ECM connector to the ECM.
- Engage the CPA retainer.
- Connect the engine wiring harness ECM connectors to the ECM.
- Engage the CPA retainer.
- If a NEW ECM was installed, the ECM must be programmed. Refer to Control Module References .
- If equipped with a manual transmission, perform the clutch pedal position sensor learn procedure. Refer to Clutch Pedal Position Sensor Learn .
Factory Service Tools
Use the Manual With the Right Hardware
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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.
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