With Generic Scan Tool

Combination valves, checking

Recommended special tools and equipment
- V.A.G 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





- Disconnect vacuum hose of the combination valve to be checked at Y - piece (arrow).






- Connect V.A.G 1390 hand vacuum pump to vacuum hose of the valve to be checked.

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

- Remove front noise insulation.






- Disconnect pressure hose (arrow) between Secondary Air Injection (AIR) Pump Motor and connecting line and blow into it with light pressure.
Both combination valves must be closed.

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

- Operate hand vacuum pump.
The respective combination valve must open.

If the combination valve does not open or it is constantly open:
- Replace the respective combination valve.