Possible causes for this code include:
* Air Injection Pump Relay: This relay controls the power to the air pump. It could be faulty or have a bad connection.
* Secondary Air Injection Pump: The pump itself could be failing, which is a common issue. It might be seized, worn out, or have internal damage.
* Air Injection Pump Wiring: A short circuit, open circuit, or damaged wiring harness can prevent the pump from functioning correctly. Check for chafing, corrosion, or broken wires, especially near the pump and relay.
* Air Injection System Solenoid Valve: This valve controls the flow of air from the pump to the exhaust manifold. It could be stuck open, stuck closed, or electrically faulty.
* Vacuum Leaks: Leaks in the vacuum lines that control the air injection system can affect its operation.
* Clogged Air Injection System Lines/Passages: Restrictions in the air lines or passages will prevent the proper flow of air.
* Faulty Air Injection System Check Valve: This valve prevents exhaust gases from backflowing into the air pump. If it fails, the pump may be damaged.
Troubleshooting Steps:
1. Visual Inspection: Start by visually inspecting the air injection pump, wiring harness, vacuum lines, and solenoid valve for any obvious damage, loose connections, or leaks.
2. Check the Relay: Locate the air injection pump relay (consult your repair manual for the location) and check its condition. You can try swapping it with a known good relay of the same type.
3. Check the Fuse: Confirm that the fuse for the secondary air injection system is not blown.
4. Check Vacuum Lines: Inspect vacuum lines for cracks, holes, or loose connections.
5. Test the Pump: You might need a multimeter to check the pump's operation and voltage. This often requires disconnecting the wiring and directly testing its functionality (consult a repair manual for detailed instructions).
6. Check the Solenoid Valve: Test the solenoid valve for proper operation. This usually involves applying voltage and checking for proper activation.
7. Check for Codes: Use an OBD-II scanner to retrieve all stored diagnostic trouble codes. There may be additional codes that provide more information.
Important Note: Diagnosing this code accurately requires some mechanical knowledge and possibly specialized tools. If you're not comfortable working on your vehicle's electrical and emission systems, it's best to take it to a qualified mechanic for diagnosis and repair. Attempting repairs without proper knowledge can lead to further damage or injury. A repair manual specific to your 2005 Chevy Trailblazer will be invaluable in this process.
