Frequency Solenoid Valve B

1. Disconnect hose No. 23 from surge tank B, then connect suitable vacuum pump to hose and draw vacuum.
2. Apply battery voltage to frequency solenoid valve B. Vacuum should be present.
3. If vacuum is present, proceed to step 5. If vacuum is not present, pinch hose between frequency solenoid valve B and constant vacuum valve.
4. If vacuum is present, replace constant vacuum valve and repeat test. If vacuum is not present, replace frequency solenoid valve B and repeat test.
5. Disconnect battery voltage from frequency solenoid valve B. Vacuum should not be present.
6. If vacuum is not present, reconnect hose No. 23 and refer to "Constant Vacuum Valve" test procedure. If vacuum is present, replace solenoid valve B and repeat test.