Air Control Valve B

1. Disconnect air suction hose from vacuum hose manifold, then blow air through the hose using a suitable vacuum pump and pressure gauge.
2. Air should not flow and gauge should register pressure.
3. If air does not flow, proceed to step 6. If air flows, remove control box cover and pinch off air suction hose to frequency solenoid valve A.
4. Blow air through air suction hose.
5. If air flows, replace air control valve B and repeat test. If air does not flow, replace frequency solenoid valve A and repeat test.
6. Disconnect vacuum hose No. 24 at surge tank B and connect vacuum pump to hose.
7. Disconnect hose between air control valve B and frequency solenoid valve A, then connect vacuum pump to pressure side of hose.
8. Apply vacuum to hose No. 24 (air control valve B-diaphragm side) and blow air into remaining hose (air control valve B-valve side). Air should flow.
9. If air flows, disconnect vacuum pumps, then proceed to "Frequency Solenoid Valve A" test procedure. If air does not flow, replace air control valve B and repeat test.