P0410

P0410
Secondary air injection signal implausible (cyl. 1-3)

Function
To improve emissions and to faster heat the Three Way Catalytic Converter (TWC), the Engine Control Module (ECM) activates the Secondary Air Injection (AIR) Pump after the engine is started and when the engine is cold, triggered by a ground signal. This, however, only happens at an engine temperature between -12°C to +60°C (temperature at engine start-up).

While the AIR system is active, the diagnosis is running. At that time the ECM is checking the voltage of the Oxygen Sensors (02S).

Diagnosis conditions
The diagnosis of the AIR system is done under the following conditions:
- The AIR pump is switched on.
- The time after engine start is between 50 sec. and 110 sec.
- Engine speed is between 720 1/min and 2800 1/min.
- Engine load is between 0.7 ms/rev. and 2.0 ms/rev.
- The air mass is not larger than 100 kg/h.
- Engine temperature is > 50°C.
- No fault at the injection final stage.
- No fault in vehicle voltage.
- No fault in fuel tank ventilation.
- No misfires harmful to TWC.
- No fault at Mass Air Flow (MAF) Sensor.
- No fault in Load recording.
- 02S Sensors 1 and 2 ahead of TWC are ready for operation.
- Throttle height adaptation is not less than 0.76.





Wiring diagram.









Diagnostic procedure
In menu "Brief test" activate Secondary Air Injection (AIR) pump with scan tool.
1. Run engine to operating temperature
2. Stop engine.
3. Start engine again.
4. In menu "Brief test" activate Secondary Air Injection (AIR) pump with scan tool.
5. Read voltage for Oxygen (02S) Sensor.

- If AIR pump starts running, and voltage does not change: Check AIR pressure valve, air supply lines and change-over valve.
- If AIR pump does not start: Check triggering of Air pump.

Check AIR pressure valve.
1. Remove two-lead connectors at AIR pressure valve and AIR pump.
2. Connect voltmeter at connector for AIR change-over valve
3. In menu "Drive Links", activate the AIR pump with scan tool.
- Display: approx. 12 V
- If no display: Remove connector X6O at relay panel in left side of engine compartment. With ohmmeter, measure between pin No. 3 of connector X6O and terminal 2 of two prong connector for change-over valve: Display: < 5 ohms
- With ohmmeter, measure between terminal 1 at 2 prong connector for change-over valve and Ground (GND). Display: < 5 ohms.

- If values are not attained: Replace wiring harness.

4. With engine running, remove vacuum hose at change-over valve. Check for vacuum.
5. Reconnect vacuum hose to change-over valve. Restore connections in engine compartment and at the change-over valve.

Checking air supply lines and change-over valve.
1. In menu "Drive Links", activate the AIR pump with scan tool.
2. Remove vacuum hose from change-over valve

- If vacuum is felt at change-over valve, check air supply lines from AIR pump to the change-over valve and to the cylinder heads: Check function of change-over valve.

Check triggering of Air pump
1. Remove relay for AIR pump from relay panel in left side of engine compartment.
2. On relay panel, bridge terminals 87 and 30 with jumper cable.

CAUTION: Pump motor switches on with high current. Use large wire gauge jumper cable.

- Pump motor starts.

3. At the free relay connector, connect voltmeter red (positive) lead to terminal 86 and black (negative) lead to vehicle ground. Switch ignition on. Display: approx. 12 V.

- If not: Repair wiring harness between relay and connector X4/1 as per wiring diagram.

4. Connect ohmmeter to free relay connector between terminal 85 and disconnected ECM connector, pin 37. Display: < 5 ohms.

- If not: Repair wiring harness between relay connector and ECM connector.

5. Connect voltmeter between terminals 85 and 86. Start engine. In menu "Drive Links" , activate the AIR pump with scan tool. approx. 12 V.

- If not: Replace ECM.
- If the pump motor does not work after bridging the AIR pump relay

6. Check fuse 48 on relay panel on left side of engine compartment.

- If fuse is OK.
7. Remove relay. Connect voltmeter positive lead to relay terminal 30 and negative lead to vehicle ground. Display: approx. 12 V.

- If not: Connect ohmmeter between relay connector terminal 30 and connector X60, pin 2. Display: < 5 ohms.

- If not: Repair wiring harness.

8. Connect ohmmeter between relay connector terminal 87 and connector pin 2 of the AIR pump. Display: < 5 ohms.

- If not: Repair wiring harness.

- If no malfunction was found when checking the wiring harness and the ECM, replace relay.