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Hot Engine

  1. Ensure engine is at normal operating temperature. Disconnect hose No. 14 from control box No. 1 and install a plug in control box No. 1. See Fig 1 and Figure .
  2. Start engine and check that frequency valves A and B are operating while running engine at 2500 RPM.
  3. Frequency valves should emit a clicking sound. It may be easier to place hand on each individual valve to feel movement. If either solenoid A or B is inoperable, replace valve and retest. If both solenoid valves operate properly, proceed to step 6).
  4. If either solenoid A or B are inoperable, check for voltage at terminal lead wires while engine is running at 2500 RPM. If voltmeter fluctuates between 12 volts and 0 volts, replace solenoid valves and retest.
  5. If voltmeter indicates 0 volts, proceed to TROUBLE SHOOTING  . If voltmeter indicates 12 volts and engine operating condition is abnormal, or the engine stops, proceed to TROUBLE SHOOTING  .
  6. Reconnect vacuum hoses. Then, with A/C, radiator fan, heater blower motor, rear window defogger and headlights off, ensure that frequency solenoid valves are inoperable while at engine is at idle speed.
  7. If solenoid valves are inoperable, the system is okay and testing is complete. If solenoid valves do operate, proceed to TROUBLE SHOOTING  .
Fig 1: Prelude Control Boxes Nos. 1 & 2
G42716