P0410

SECONDARY AIR INJECTION SYSTEM, INCORRECT FLOW





Fault Symptom.
CHECK ENGINE lamp (MIL) on.

Conditions.
^ Diagnosis not yet performed this trip.
^ Speed = 0.
^ Idling speed
^ Closed loop active
^ Engine coolant temperature < 55°C (132°F) and

P0410 (large flow)
Closed loop > 25% for 20 seconds.

P0411 (small flow)
Secondary air injection pump and closed loop increase < 12 percentage points within 12 seconds.

Diagnostic Help.
A diagnosis of the secondary air injection system can be obtained with the ISAT scan tool.

- Select "INITIATE".
- Select "SLS DIAGNOSIS".
- On completion of diagnosis the ISAT scan tool will show "READY",
Otherwise "NOT READY".

The secondary air injection system can be activated with the ISAT scan tool.
- Select "ACTIVATE".
- Select "SECOND. AIR RELAY'.

The pump will be activated at a frequency of 0.5 Hz for 30 seconds.

Check The Wiring.
Intermittent faults may occur as a result of temporary short circuits and breaks in the wiring. Jiggle the wiring at several points and in different directions to ascertain whether the wiring harness, including any connectors, is causing the trouble. Observe the multimeter, ISAT scan tool or test lamp while doing this.





Diagnostic Procedure.
1 Check other Motronic 4.1 diagnostic trouble codes

- Connect an ISAT scan tool.
- Turn the ignition switch to the ON position.
- Select "READ FAULT CODES".

Does the ISAT scan tool show diagnostic trouble code P1680?

YES:
^ Continue fault diagnosis with P1680.

NO:
^ Continue with point 2.

2 Check the fuses

- Check that fuse 12 and MAXI-fuse 3 are intact. The fuses are on the fuse board, main fuse box in the engine bay.

Are the fuses intact?

YES:
^ Continue with point 3.

NO:
^ Change the blown fuse. Continue with point 3.





3 Check the performance of the secondary air injection pump

- Turn the ignition switch to the ON position.
- Select "ACTIVATE".
- Select "SECOND. AIR RELAY". See Diagnostic help.

The command activates the two relays of the secondary air injection system at a frequency of 0.5 Hz for 30 seconds.

Is the secondary air injection pump working?

YES:
^ Continue with point 9.

NO:
^ The secondary air injection pump is not working and MAXI-fuse 3 has blown. Continue with point 8.

NO:
^ he secondary air injection pump is not working but MAXI-fuse 3 is still intact. Continue with point 4.

4 Check the switching function of the secondary air Injection pump relay.

- Remove the secondary air injection pump relay.
- Forcibly run the secondary air injection pump by connecting a jumper lead in the relay base between:
^ pins 30 and 87.

The secondary air injection pump should run continuously.

Is the secondary air injection pump working?

YES:
^ Continue with point 5.

NO:
^ Continue with point 8.





5 Check the relay, secondary air injection pump control current

- Connect the test lamp to:
^ pin 86 of the relay socket and battery negative (B-).
- Turn the ignition switch to the ON position.
- Select "ACTIVATE".
- Select "SECOND. AIR RELAY".
The test lamp should flash at a frequency of 0.5 Hz for 30 seconds.

Test lamp flashing?

YES:
^ Continue with point 6.

NO:
^ Continue with point 7.





6 Check the operation of the relay, secondary air injection pump

- Connect the test lamp to the relay socket between:
^ Pins 86 and 85.
- Turn the ignition switch to the ON position.
- Select "ACTIVATE".
- Select "SECOND. AIR RELAY".
The test lamp should flash at a frequency of 0.5 Hz for 30 seconds.

Test lamp flashing?

YES:
^ Change the secondary air injection pump relay. Continue with point 11.

NO:
^ Check and if necessary repair or replace the lead between pin 85 of the relay socket and grounding point G30. Continue with point 11.





7 Check the switching function of the relay, secondary air injection control valve

- Refit the secondary air injection pump relay.
- Remove the secondary air injection control valve relay.
- Connect the test lamp to:
^ pin 30 of the relay socket and battery negative (B-).
The test lamp should light up.
- Connect a jumper lead to the relay socket between:
^ pins 30 and 87.
The secondary air injection pump should run continuously.

Is the secondary air injection pump working?

YES:
^ Change the secondary air injection control valve relay. Continue with point 11.

NO:
^ Check and if necessary repair or replace the lead between:
- pin 30 of the relay socket and fuse 12.
- pin 87 of the relay socket and pin 86 of the secondary air injection pump relay. Continue with point 11.





8 Check the secondary air injection pump

- Connect the test lamp to:
^ pin 30 of the relay socket and battery negative (B-).
The test lamp should light up.
- Unplug the secondary air injection pump's 2-pin connector.
- Connect the test lamp to the female connector between:
^ Pins 1 and 2.
- Connect a jumper lead to the relay socket between:
^ pins 30 and 87.

The test lamp should light up.

Did the test lamp light up?

YES:
^ Change the secondary air injection pump. Continue with point 11.

NO:
^ Check and if necessary repair or replace the lead between:
- pin 30 of the relay socket and MAXI-fuse 3
- pin 87 of the relay socket and pin 2 of the secondary air injection pump's connector
- pin 1 of the secondary air injection pump's connector and grounding point G30. Continue with point 11.





9 Check the hose system

- Disconnect the hose from the exhaust manifold's non-return valve.
- Disconnect the hose from the secondary air injection control valve and connect it to a vacuum pump. The hose is on the side facing towards the front of the car (towards the vacuum valve).
- Turn the ignition switch to the ON position.
- Select "ACTIVATE".
- Select "SECOND. AIR RELAY'.
The secondary air injection pump should work but it should not blow air into the thick hose.
- Use the vacuum pump to build up a vacuum. The pump should now blow air into the hose.

Is the hose system OK?

YES:
^ Continue with point 10.

NO:
^ Change the vacuum valve. Continue with point 11.





10 Check the secondary air injection control valve

- Disconnect the vacuum hose from the secondary air injection control valve's inlet pipe.
- Connect a vacuum pump to the control valve.
- Use the vacuum pump to build up a vacuum.
- Check that the control valve does not leak.
- Turn the ignition switch to the ON position.
- Select "ACTIVATE".
- Select "SECOND. AIR RELAY".

The vacuum should disappear.

Is the system OK?

YES:
^ Continue with point ii.

NO:
^ Change the secondary air injection control valve. Continue with point 11.





11 Final check

Use the ISAT scan tool to activate diagnosis of the secondary air injection system. For diagnosis to be carried out, the following conditions must be fulfilled:

^ The secondary air injection system must have been activated at the start of this trip.
^ Diagnosis not yet performed this trip.
^ Speed = 0.
^ Idling speed.

Perform diagnosis:

- Connect an ISAT scan tool.
- Clear the fault codes.
- Select "INITIATE".
- Select "SLS DIAGNOSIS".
- Wait for about 2 minutes or until the ISAT scan tool reads "READY".
- Obtain a readout of the diagnostic trouble code.

Has the diagnostic trouble code recurred?

YES:
^ Continue at "Before Replacing a Control Module". Component Tests and General Diagnostics

NO:
^ The steps taken to rectify the fault were correct.