Secondary Air Injection Solenoid Valve, Checking

Secondary Air Injection Solenoid Valve, Checking

Special tools, testers and auxiliary items required

• Multimeter.

• Wiring diagram.

Test requirements

• Fuse (S73) OK.

• The ignition switched off.

• Voltage for the Secondary Air Injection (AIR) Solenoid Valve (-N112-) is supplied by the Fuel Pump (FP) Relay (J17).

Test procedure

- Perform a preliminary check to verify the customers complaint. Refer to => [ Preliminary Check ] Preliminary Check.

Start diagnosis

- Disconnect the Secondary Air Injection (AIR) Solenoid Valve (-N112-) electrical harness connector.

Checking internal resistance

- Using a Multimeter, check the Secondary Air Injection (AIR) Solenoid Valve (-N112-) terminals 1 and 2 for resistance.





Specified value: 25 to 35 ohms.

If the specified value is not obtained:

- Replace the Secondary Air Injection (AIR) Solenoid Valve (-N112-).

If the specification is obtained:

Checking voltage supply

- Using a Multimeter, check the Secondary Air Injection (AIR) Solenoid Valve (-N112-) electrical harness connector terminal 1 to Ground (GND) for voltage.









- Operate the starter briefly.

Specified value: battery voltage.

If the specified value was not obtained:

- Check the wiring connection from the Secondary Air Injection (AIR) Solenoid Valve (-N112-) electrical harness connector terminal 1 to Fuel Pump Relay (J17) socket 30/87F for an open circuit or a short to Battery positive (+).

- Check the electrical harness connector for damage, corrosion, loose or broken terminals.

- If necessary, repair the wiring connection.

If the specified value was obtained:

Check Ground (GND) activation

- Using a Multimeter, check the Secondary Air Injection (AIR) Solenoid Valve (-N112-) electrical harness connector terminal 2 to Battery (+) for voltage.









- Operate the starter briefly.

Specified value: battery voltage.

- Switch the ignition off.

If the specified value was not obtained:

- Check the wiring connection from the Secondary Air Injection (AIR) Solenoid Valve (-N112-) electrical harness connector terminal 2 to the Motronic Engine Control Module (ECM) ( J220) electrical harness connector terminal 44 for an open circuit or a short to Battery positive (+).

- Check the electrical harness connector for damage, corrosion, loose or broken terminals.

- If necessary, repair the wiring connection.

If the specified value was obtained:

Checking wiring

If the manufacturers test box is being used, perform the following step.

- Install the test box (VAG1598/31). Refer to Fuel Injection and Ignition Repair Information

If the manufacturers test box is not being used, perform the following step.

- Remove the Motronic Engine Control Module (ECM) ( J220). Refer to => [ Engine Control Module, Replacing ] Engine Control Module, Replacing.

- Using a Multimeter, check the Secondary Air Injection (AIR) Solenoid Valve (-N112-) electrical connector terminal 2 to Motronic Engine Control Module (ECM) (J220) electrical connector terminal 44 for an open circuit.





Specified value: 1.5 ohms max.

If the specification is not obtained:

- Check the wiring for a short circuit to each other, to Battery positive (+), Ground (GND) or an open circuit.

- Check the electrical harness connector for damage, corrosion, loose or broken terminals.

- If necessary, repair the wiring connection.

- Erase the DTC memory. Refer to => [ Diagnostic Mode 04 - Erase DTC Memory ] Diagnostic Mode 04 - Erase DTC Memory.

- Perform a road test to verify repair.

If the DTC does not return:

Repair complete, Generate readiness code. Refer to => [ Readiness Code ] Readiness Code.

- End diagnosis.

If the DTC does return and no malfunction is detected in the wiring and the voltage supply was OK:

- Replace the Motronic Engine Control Module (ECM) (J220). Refer to => [ Engine Control Module, Replacing ] Engine Control Module, Replacing.

- Assembly is performed in the reverse of the removal.

Final procedures

After the repair work, the following work steps must be performed in the following sequence:

1. Check the DTC memory. Refer to => [ Diagnostic Mode 03 - Read DTC Memory ] Diagnostic Mode 03 - Read DTC Memory.

2. If necessary, erase the DTC memory. Refer to => [ Diagnostic Mode 04 - Erase DTC Memory ] Diagnostic Mode 04 - Erase DTC Memory.

3. If the DTC memory was erased, generate readiness code. Refer to => [ Readiness Code ] Readiness Code.

End diagnosis.