P0411
P0410
Secondary Air Injection Signal Implausible (cylinders 1 - 3).
P1411
Secondary Air Injection Signal Implausible (cylinders 4 - 6).
Function:
To improve emissions and to heat the three-way catalytic converter (TWC) faster, the secondary air injection pump activated after the engine is started when the engine is cold, thus blowing secondary air behind the discharge valves. If the engine temperature at start-up is less than -10 °C, the secondary air injection pump is disabled until the engine temperature has reached more than 44°C. If the engine is started in a temperature range between -10°C and 60°C, the secondary air injection system is activated for a time depending on the start-up temperature
The secondary air injection system is deactivated under the following conditions:
Engine load > 4.5 ms
Air mass > 300 kg/h
Engine speed > 3800 rpm
A distinction is made between active and passive diagnosis. With passive diagnosis, testing is performed during the actual secondary air injection function. The sensor voltages ahead of the three-way catalytic converter are evaluated. If passive diagnosis is interrupted, active diagnosis takes place with the engine idling. The secondary air injection pump is switched on for this purpose. The deviation of the oxygen sensors due to the excess oxygen is evaluated.
Diagnosis Conditions:
Passive diagnosis of the secondary air injection system is carried out under the following conditions:
- Diagnosis has not yet been carried out in this cycle.
- The secondary air injection pump is switched on.
- The time after engine start-up is between 50 seconds and 179 seconds.
- Engine speed is between 680 rpm and 2800 rpm.
- Engine load is between 0.7 ms and 3.0 ms.
- Air mass < 100 kg/h.
- Engine temperature > 30°C.
- Vehicle must not be at an altitude above 2448 m above sea level.
- No fault at the injection final stages.
- No fault in the voltage supply.
- No fault in fuel tank ventilation.
- No misfires harmful to TWC.
- No fault at Mass Air Flow (MAF) sensor.
- No fault in load recording.
- Oxygen sensors 1 and 2 ahead of TWC are ready for operation.
Active diagnosis of the secondary air injection system is carried out under the following conditions:
- No diagnosis with result yet.
- Secondary air injection function already performed in this driving cycle.
- Engine temperature between 10°C and 95°C.
- Intake air > -10°C.
- Oxygen sensing active.
- Idle speed.
- Stationary vehicle.
- No final stage faults in EVAP canister purge valve, secondary air injection pump and secondary air valve.
- No fault in fuel tank ventilation system, mass air flow sensor, in the voltage supply, throttle position sensor, oxygen sensor aging, engine temperature sensor and intake air temperature sensor.
- No misfires harmful to TWC.
Wiring Diagram
System Overview
Diagnostic Procedure:
1. In menu "Drive links", trigger secondary air injection (AIR) pump.
1. Connect and switch on Porsche System Tester 2.
2. Select DME.
3. Call up menu "Drive links".
4. Select AIR pump.
5. Activate AIR pump.
2. Check triggering of AIR pump.
1. Check fuse for AIR pump (on relay carrier 2).
2. Remove relay for AIR pump (on relay carrier 2). Connect voltmeter to pin 3 and ground.
Display: Battery positive voltage.
Connect voltmeter to pin 2 (negative) and pin 7 (positive). Start engine (the ECM relay must pick up).
Display: Battery positive voltage.
If 0 Volt is displayed, check wire from pin 2 to ECM pin 37 for continuity.
Push on relay again.
3. Remove connector on AIR pump.
Connect voltmeter to pin 1 (positive) and pin 2 (negative). Trigger AIR pump with Porsche System Tester 2.
Display: Battery positive voltage.
3. Check electric change-over valve.
1. Remove two-pole connector at change over valve.
2. Connect voltmeter to pin 1 (positive) and pin 2 (negative).
3. Trigger AIR pump with Porsche System Tester 2.
Display: Battery positive voltage.
4. Remove vacuum hose on change over valve with the engine running. Check whether vacuum is present.
4. Check air change-over valve and air supply lines.
1. Run engine briefly to produce vacuum.
2. Trigger AIR pump with Porsche System Tester 2.
3. Remove vacuum hose on air change-over valve.
If a vacuum is present at the air change-over valve, check air supply from the AIR pump up to the change over valve up to the air supply line to the cylinder heads.
Check function of air change over valve.