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Fuel Injector Circuit Diagnosis

CIRCUIT DESCRIPTION
The powertrain control module (PCM) enables the appropriate fuel injector on the intake stroke for each cylinder. A voltage is supplied directly to the fuel injectors. The PCM controls each fuel injector by grounding the control circuit via a solid state device called a driver.

DIAGNOSTIC AIDS
^ Monitoring the fuel injector circuit status with a scan tool, while moving the fuel injector harness, may help isolate an intermittent condition.
^ Performing the Fuel Injector Coil Test may help isolate an intermittent condition. Refer to Fuel Injector Coil Test. Component Tests and General Diagnostics
^ For an intermittent condition, refer to Intermittent Conditions. Intermittent Conditions

TEST DESCRIPTION

Fuel Injector Circuit Diagnosis - Steps 1-8:




The numbers below refer to the step numbers on the diagnostic table.
3. This step tests for an open ignition 1 voltage supply circuit between the PCM 1 fuse and the multi-way connector.
4. This step tests for an open or high resistance between the multi-way connector and the fuel injectors.