Diagnosing and resolving air injection pump (AIR) issues in your 2006 GMC Yukon 1500 requires systematic troubleshooting. Common symptoms include illumination of the Check Engine Light with codes P0410, P0412, or P0418, accompanied by rattling noises near the passenger-side front wheel.
Diagnosis Tools
- OBD-II scanner to retrieve specific diagnostic codes
- Multimeter for continuity and voltage checks
- Vacuum gauge for line integrity testing
Key Diagnostic Steps
Air Pump Circuit Testing:
- Locate the AIR pump beneath the battery tray. Disconnect the electrical connector.
- Check for 12V power at the red/white wire (KOEO). If absent, inspect fuse #48 (40A) in the underhood fuse block.
- Verify ground circuit continuity at the black wire using a multimeter.
Component Function Test:
- Apply 12V directly to pump terminals with fused jumper wires. Functional pumps produce immediate airflow.
- Inspect rubber hoses connecting pump to check valve and manifold for dry rot (common failure point).
- Test vacuum actuator operation by applying engine vacuum to the control solenoid.
Check Valve Inspection:
- Trace the metal tubing from pump to exhaust manifold check valve. Remove valve and verify it permits airflow only toward the manifold.
- Shake valve – rattling indicates internal failure requiring replacement (GM part # 12623454).
Common Failure Points
- Corroded pump terminals due to battery proximity
- Split vacuum lines at the control solenoid
- Seized pump bearings from water intrusion
- Fractured plastic air diverter valves
Replacement Notes
- When installing new pumps (ACDelco 215-211 recommended), apply dielectric grease to electrical contacts.
- Prime replacement pumps by running for 60 seconds with outlet disconnected.
- Clear ECM codes after repair – allow three drive cycles for readiness monitor reset.