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Home >> Saturn >> 2002 >> SC2 Automatic, MP6 >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Self-Diagnostics >> Diagnostic Tests >> DTC P0621: Gen Terminal L Circuit >> Diagnostic Procedures
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Diagnostic Procedures

  1. Start engine and run for one minute. Using scan tool, monitor LAST TEST for DTC P0621. If LAST TEST failed, go to next step. If LAST TEST did not fail, problem is intermittent. See DIAGNOSTIC AIDS  .
  2. Turn ignition on, engine off. Disconnect generator terminal "L" connector. Using DVOM, measure voltage on terminal "L" circuit (Brown/White wire) at connector. If voltage is 4-6 volts, go to next step. If voltage is not 4-6 volts, repair short to ground in Brown/White wire or faulty PCM.
  3. With generator terminal "L" disconnected, start engine and run for one minute. Using scan tool, monitor status of DTC P0621. If LAST TEST passed, check charging system. See appropriate GENERATORS & REGULATORS article in STARTING & CHARGING SYSTEMS. If LAST TEST did not pass, replace PCM.
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