2003 Hummer H2FACTORY OEM SERVICE PROCEDURE

No. 1 Additional Key Registration Procedure (Using Two Valid Keys): Conditions

WARNING: This page is about a different car, the 2004 Mazda 3. However, it is still accessible from the selected car via links, so may be relevant.
  • Customer has two or more valid keys.
    NOTE:
    • A maximum of eight keys can be registered for any one vehicle. If key registration is not successful and DTC 15 appears even though the procedure was performed properly, use the PID/data monitor function of the WDS or equivalent and verify the number of keys that have been registered.
    • If eight keys have already been registered, and it is necessary to register other keys, the previously registered key ID numbers must first be cleared. To clear the key ID numbers, refer to "09-14-26 No.3 Key Replacement Procedure (Clearing Previously Registered Key ID Numbers, Key Re-registration)".
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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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