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A/C Idle Control Solenoid Valve: Prelude

  1. A/C idle control solenoid valve is activated when A/C switch is turned on. When solenoid valve is activated, vacuum is applied to hose No. 19 between solenoid valve and idle diaphragm.
  2. When solenoid valve is activated, 9 volts or more should be available between Black/Yellow (A) terminal and Blue/Yellow (Red on Prelude) (B) terminal of control box No. 2 harness.
  3. Disconnect wiring harness from No. 2 control box. Disconnect vacuum hose No. 19 from air flow tube. Start engine and check for vacuum at solenoid valve fitting. Vacuum should not be present.
  4. Connect battery positive terminal to Black terminal of Control Box No. 2 connector and battery negative terminal to Blue terminal. Start engine and check for vacuum at solenoid valve fitting. Vacuum should be present.
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