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Power Valve Control Solenoid Valve

  1. Disconnect solenoid valve No. 14 vacuum hose from vacuum hose manifold and connect a hand-held vacuum gauge. See Fig 1 . Start engine. If vacuum is present, turn ignition off and go to next step. If vacuum is not present, go to step 4).
  2. Disconnect 4-pin connector near solenoid valve. Start engine. Measure voltage between Green/Yellow (positive) terminal and Black (negative) terminal on wire harness. See Fig 1 . If battery voltage is present, replace solenoid valve. If battery voltage is not present, measure voltage between Green/Yellow (positive) terminal and body ground.
  3. If battery voltage is present, repair open or short in Black wire between solenoid valve and ground. If battery voltage is not present, check CHECK ENGINE light and self-diagnosis indicator. If okay, check for open or short in Green/Yellow wire between control box and control unit.
  4. Warm engine to normal operating temperature (cooling fan comes on). Check vacuum gauge. If vacuum is present, solenoid valve is okay. If vacuum is not present, turn ignition off. Disconnect 4-pin connector near solenoid valve. See Fig 1 Start engine. Measure voltage between Green/Yellow (positive) terminal and Black (negative) terminal on wire harness.
  5. If battery voltage is present, replace solenoid valve. If battery voltage is not present, check CHECK ENGINE light and self-diagnosis LED indicator. If voltage is present, substitute a known good control unit and retest. If symptom goes away, replace original control unit.
    Fig 1: Testing Power Valve Control Solenoid Valve
    G90A17129Courtesy of AMERICAN HONDA MOTOR CO., INC.