Secondary Air Injection (AIR) Solenoid Valve -N112-, Checking

Secondary Air Injection (AIR) Solenoid Valve -N112-, Checking

Special tools and equipment
- V.A.G 1526A
- V.A.G1527B
- V.A.G 1594A
- V. A. G 1598/31
- VAS5051
or
- V.A.G 1551 with V.A.G 1551/3A

Test requirement:
- Output Diagnostic Test Mode (DTM) performed

Checking internal resistance
- Disconnect harness connector from Secondary Air Injection (AIR) valve -N112-.

- Connect multimeter at valve for resistance measurement.

- Specified value: 25 - 35 Ohms

- If specified value is not obtained, replace Secondary Air Injection (AIR) solenoid valve -N112-.

Checking voltage supply
- Disconnect harness connector from Secondary Air Injection (AIR) valve -N112-.

- Connect V.A.G 1527B voltage tester as follows:

Harness connector terminal Measure to
1 Engine Ground (GND)

- Operate starter briefly (engine can also start).
- LED must light up.

If LED does not light up:
- Perform the following tests marked with dots:

- Check fuse -S243- (in fuse holder, position 43).

- Check wire connection from terminal 1 of connector via fuse -S243- (in fuse holder, socket 43) to Fuel Pump (FP) relay for open circuit

- Check Fuel Pump (FP) relay

Checking activation

- Connect V.A.G 1527B voltage tester as follows:

Harness connector terminal Measure to
2 B+

- Initiate output Diagnostic Test Mode (DTM) and activate Secondary Air Injection (AIR) solenoid valve -N112-, Output Diagnostic Test Mode (Function 03)

Indicated on display
Output Diagnostic Test Mode ->
Secondary air injection solenoid valve -N112

- LED must blink.

If LED does not blink or if it remains constantly lit:
- Connect V.A.G 1598/31 test box at wiring harness to ECM, do not connect ECM.

- Check the following wire connections for open circuit and short circuit to Ground (GND) and B-:

Harness connector terminal V.A.G 1598/31 testing box Bushing
2 9

- Repair open circuit or short circuit if necessary.
- If wire connection is OK: Replace Engine Control Module (ECM)