TrailBlazer 4WD L6-4.2L (2007)
Fuel Injector: Testing and Inspection
Fuel Injector Circuit Diagnosis
Fuel Injector Circuit Diagnosis
Circuit Description
The control module enables the appropriate fuel injector pulse for each cylinder. Ignition voltage is supplied to the fuel injectors. The control module
controls each fuel injector by grounding the control circuit via a solid state device called a driver.
Diagnostic Aids
* A short to battery voltage or ignition 1 voltage on the MAP sensor signal circuit will disable the injector control circuits.
* 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 Diagnosis (w/J39021 or Tech 2) See: Computers and Control Systems/Testing and Inspection/Component Tests and
General Diagnostics/Fuel Injector Diagnosis (w/J39021 or w/Tech 2)
Refer to Fuel Injector Diagnosis (w/CH47976). See: Computers and Control Systems/Testing and Inspection/Component Tests and General
Diagnostics/Fuel Injector Diagnosis (With CH 47976)
* For an intermittent condition, refer to Intermittent Conditions. See: Computers and Control Systems/Testing and Inspection/Initial Inspection and
Diagnostic Overview/Intermittent Conditions
Test
Step 1 - Step 8
