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Home >> Ford >> 1995 >> RV Cutaway 7.3 F >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - System/Component Tests - EEC-IV (7.3L Diesel) >> Component Tests >> Glow Plug Testing >> Functional Test
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Functional Test

  1. With ignition off, connect a 12-volt test light between glow plug module test terminal and ground. See Figure . Position test light so that it can be seen from driver's seat. Turn ignition switch to ON position and monitor test light. Compare test light times to chart. See Fig 1 . Total test light ON time includes time from the beginning of the initial ON cycle to the end of the last ON-OFF cycle measured in seconds.
    NOTE: The WAIT-TO-START indicator and/or test light may not illuminate if engine temperature is at or near operating temperature.
  2. If test light times are within specifications, system is functioning correctly and test is complete. If test light times are not within specifications, disconnect both batteries and replace glow plug module. Repeat FUNCTIONAL TEST.
Fig 1: 7.3L Glow Plug Module Functional Test Chart
G91C13450Courtesy of FORD MOTOR CO.