For 1990-2009 cars

The secondary air injection (AIR) system is used to accelerate the heating process of the catalytic converters by introducing outside air into the exhaust manifold. The air pump operates on cold engine starts when the catalytic converters work least efficient. The air pump solenoid is used to control manifold vacuum to the combination valve. When the air pump solenoid is energized (PCM supplies ground), manifold vacuum will pull the combination valve up and allow air from the air pump to flow into the exhaust manifold. The powertrain control module (PCM) monitors the air pump solenoid circuit for low and high voltage faults. DTC P0413 sets when the air pump solenoid is commanded OFF and the feedback voltage at the PCM is low.

### DTC Parameters

DTC P0413 will set if air pump solenoid feedback voltage is less than 1.25 volts with air pump solenoid commanded OFF when:

• | The condition exists for longer than 0.5 seconds.

• | The ignition is ON.

DTC P0413 diagnostic runs continuously with ignition ON and air pump solenoid commanded OFF.

DTC P0413 is a type D DTC.

### Diagnostic Aids

To locate an intermittent problem, use a scan tool to monitor the AIR PUMP SOL. - LOW VOLT or AIR PUMP SOL. - OPEN test with ignition ON, engine OFF. When a fault (open or short to ground) exists, the scan tool will display TEST FAIL for both tests.

The tests will fail only when the device is being commanded OFF and the voltage at the PCM is low. The tests update every 100 ms whenever the ignition is turned ON and the device is being commanded OFF via the scan tool or PCM.

The air pump solenoid resistance is 38-61 ohms.