Check Engine LightIlluminated, DTC P0411 (Replace Secondary Air Inject. Check Valve)

Some customers may comment that the Check Engine Light is illuminated.

The 1997-1999 Catera may experience intermittent or repeat DTC P0411 for the secondary air injection (AIR) system. In many instances, the dealer may not be able to duplicate this condition.

This condition may be due to a partially or completely restricted air check valve. The check valve contains four reed valves. If one or more of the reed valves are stuck closed, this will restrict the air flow enough for DTC P0411 to set.

1. Install the Tech 2 to the vehicle DLC and check for DTC's.
2. Diagnose all other ECU DTCs prior to diagnosing the P0411.
3. Use the latest version of SI 2000 to diagnose all DTC's.
4. When the causes of all other DTC's have been corrected, begin the P0411 diagnosis.
5. For DTC P0411 diagnosis, use the latest version of SI 2000.

Important: The air pump on the Catera is equipped with an internal circuit breaker designed to protect the air pump from overheating. Prolonged or repeated testing of pump operation with the Tech 2 may cause the circuit breaker to open, rendering the pump inoperative. DO NOT replace the pump if this occurs. The pump will resume normal operation when the internal temperature cools sufficiently.

A new diagnostic aid has been added to the Tech 2 recently which will allow the AIR system to be operated using a Service Bay Test for 1999 model year vehicles. This feature is not available for the 1997-1998 model year vehicles. The Tech 2 scan tool will command the ECU to run the on-board diagnostics for the AIR system. If the condition is present, the ECU will set the appropriate DTC.

If the diagnosis points to the secondary air injection check valve as the cause of DTC P0411, replace the valve with P/N 09196528 for model year 1997-1999 vehicles.

The Service Information is not designed to diagnose vehicles that have been serviced with incorrect components. The following table is to help identify vehicles with previously installed incorrect components.

Parts are currently available from GMSPO.

For vehicles repaired under warranty, use: