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Chart A-4

NOTE: Test numbers refer to test numbers on diagnostic chart.
  1. No fuel spray from injector indicates faulty fuel system or no ECM control of injector. If test light "blinks" while cranking, ECM control is considered okay. Light may dim while "blinking", use bulb 1847 or equivalent.
  2. Circuits 481 and 482 supply ignition voltage to injectors. Probe Each connector terminal with test lamp connected to ground. There should be light on one terminal. If test lamp confirms ignition voltage at connector, then ECM injector control circuit 467 or 468 may be open. Reconnect injector and using test lamp connected to ground, check for light at applicable ECM connector (terminal D14 or D16). Light at this point indicates that injector drive circuit involved is okay. If ECM repeat failure has occurred, injector is shorted. Replace injector and ECM.
Fig 1: Chart A-4, Engine cranks but will not run
G15415