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System Testing

  1. If trouble codes exist and diagnostic circuit check has been performed, compare code with appropriate code chart for circuits and components associated with trouble code(s). Trouble code flow charts are arranged in alphabetical order by each model. A test No. has been assigned each chart. The test No. and trouble code are in numerical order for each model. All ECU pin identifications are at end of TROUBLE CODES & PROBABLE CAUSE  charts.
  2. If no code is present, circuit checking is necessary. Each model has an ECU PIN VOLTAGE TEST table after DIAGNOSTIC CIRCUIT CHECK  flow chart. DIAGNOSTIC CIRCUIT CHECK  flow chart is the first flow chart on each model. Using ECU PIN VOLTAGE TEST table, check appropriate circuits using the test No. in the right column of the appropriate table.
  3. Component testing will also be necessary. All component testing available from manufacturer and pertaining to CEC, follow the CEC flow charts. For components not covered, see appropriate article in FUEL or DISTRIBUTORS & IGNITION SYSTEMS.
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