G6 L4-2.4L (2007)
Fuel Injector: Testing and Inspection
Fuel Injector Circuit Diagnosis
Fuel Injector Circuit Diagnosis
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. See: Testing and Inspection/Initial Inspection and
Diagnostic Overview/Diagnostic Starting Point - Vehicle
* Review Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions provides an overview of each diagnostic category.
Diagnostic Fault Information
Circuit/System 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.
Circuit/System Testing
1. Ignition OFF, disconnect the harness connector at a fuel injector.
2. Ignition ON, verify that a test lamp illuminates between the ignition circuit terminal A and ground.
‹› If the test lamp does not illuminate, test the ignition circuit for a short to ground or an open/high resistance. If the circuit tests normal and the
ignition circuit fuse is open, test or replace the fuel injector.
3. Ignition OFF, connect a J 44603 between the control circuit terminal B and the ignition circuit terminal A of each fuel injector one at a time.
4. Engine cranking, the test lamp should flash for each injector.
‹› If the test lamp is always ON, test the appropriate control circuit for a short to ground. If the circuit tests normal, replace the engine control
module (ECM).
‹› If the test lamp is always OFF, test the appropriate control circuit for a short to voltage or an open/high resistance. If the circuit tests normal,
replace the ECM.
5. If all circuits test normal, test or replace the fuel injector. Refer to Fuel Injector Diagnosis (w/J39021 or w/Tech 2) Fuel Injector Diagnosis
(w/CH47976). See: Computers and Control Systems/Testing and Inspection/Component Tests and General Diagnostics/Fuel Injector Diagnosis
(w/J39021 or w/Tech 2) See: Computers and Control Systems/Testing and Inspection/Component Tests and General Diagnostics/Fuel Injector
Diagnosis (With CH 47976)
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
* Control Module References See: Testing and Inspection/Programming and Relearning
* Fuel Injector Replacement See: Computers and Control Systems/Testing and Inspection/Diagnostic Trouble Code Tests and Associated
Procedures/Verification Tests and Procedures
