Combination Valve, Checking

Combination Valve, Checking

Vehicles with engine code AEG up to 05.99:

Recommended special tools and equipment

- VAG 1390 Hand Vacuum Pump

Test requirements

- No leaks in vacuum lines or hose connections.
- Vacuum hoses not clogged or kinked
- Pressure hose for Secondary Air Injection (AIR) Pump Motor not clogged or kinked

Test sequence

NOTE: Do not use pressurized air for the following test.

- Remove front noise insulation.







- Disconnect vacuum hose -1- from combination valve at Secondary Air Injection (AIR) solenoid valve (N112) -2-.
- Connect hand vacuum pump (VAG1390) at vacuum hose -1- to combination valve.
- Disconnect pressure hose at Secondary Air Injection (AIR) pump motor (arrow) and blow into it with light pressure. Combination valve must close.

NOTE: To disengage, compress the buttons at the hose coupling.

- Operate vacuum pump. Combination valve must open.

If the combination valve does not open or it is constantly open:
- Replace combination valve, item 20.
- Erase DTC memory of Engine Control Module (ECM), Diagnostic mode 4: Reset/erase diagnostic data. Diagnostic Mode 4: Reset/Erase Diagnostic Data
- Generate readiness code. Monitors, Trips, Drive Cycles and Readiness Codes

Vehicles with engine code AEG as of 06.99, AVH, AZG, BDC

Test requirements
- Pressure hose for Secondary Air Injection (AIR) Pump Motor not clogged or kinked.
- Hose connections must be properly sealed.

Test sequence


NOTE: Do not use pressurized air for the following test.


- Remove front noise insulation.







- Disconnect pressure hose (arrow) from Secondary Air Injection (AIR) pump motor.

NOTE: To disengage, compress the buttons at the hose coupling.

- Blow with light pressure into pressure hose to combination valve. Combination valve must close.
- Blow with high pressure into pressure hose to combination valve. Combination valve must open.

If the combination valve does not open or it is constantly open:
- Replace the combination valve:
- Vehicles with engine code AEG, AVH, AZG, item 20,
- Vehicles with engine code BDC, item 1.
- Erase DTC memory of Engine Control Module (ECM), Diagnostic mode 4: Reset/erase diagnostic data. Diagnostic Mode 4: Reset/Erase Diagnostic Data
- Generate readiness code. Monitors, Trips, Drive Cycles and Readiness Codes