Air Vacuum Switching Valve

Vacuum Switching Valve:

1. Remove VSV.
2. Connect vacuum pump to port "B."
3. Block port "A" with finger tip and apply vacuum to port "B." No vacuum should be felt at port "A," and port "B" should be vented to the atmosphere (does not hold vacuum).
4. Energize solenoid by applying 12 volts DC.
5. Block port "A" with finger tip and apply vacuum to port "B." You should feel vacuum at port "A" and valve should hold vacuum until port "A" is opened.
6. Replace if defective.

NOTE: When re-installing VSV, be sure port "B" is connected to device and port "A" is connected to vacuum source. If connected improperly, a vacuum leak will result.