HHR L4-2.4L (2010)
Fuel Injector: Testing and Inspection
Fuel Injector Solenoid Coil Test
Fuel Injector Solenoid Coil Test
Diagnostic Instructions
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Perform the Diagnostic System Check - Vehicle (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic System
Check - Vehicle) prior to using this diagnostic procedure.
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Review Strategy Based Diagnosis (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Strategy Based Diagnosis) for an
overview of the diagnostic approach.
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Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure Instructions
)provides an overview of each diagnostic category.
Circuit/System Description
The control module enables the appropriate fuel injector pulse for each cylinder. The ignition voltage is supplied directly to the fuel injectors. The
control module controls each fuel injector by grounding the control circuit via a solid state device called a driver. A fuel injector coil winding resistance
that is too high or too low will affect the engine driveability. A fuel injector control circuit DTC may not set, but a misfire may be apparent. The fuel
injector coil windings are affected by temperature. The resistance of the fuel injector coil windings will increase as the temperature of the fuel injector
increases.
Reference Information
Schematic Reference
Engine Controls Schematics (See: Diagrams/Electrical Diagrams)
Connector End View Reference
Component Connector End Views (See: Diagrams/Connector Views)
Electrical Information Reference
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Circuit Testing (See: Testing and Inspection/Component Tests and General Diagnostics/Circuit Testing/Circuit Testing)
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Connector Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/Connector Repairs/Connector Repairs)
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Testing for Intermittent Conditions and Poor Connections (See: Testing and Inspection/Component Tests and General Diagnostics/Circuit
Testing/Testing for Intermittent Conditions and Poor Connections)
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Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/Wiring Repairs/Wiring Repairs)
Component Testing
Verify the resistance of each fuel injector with one of the following methods:
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If the engine coolant temperature (ECT) sensor is between 10-32°C (50-90°F), the resistance of each fuel injector should be 11-14 ohm.
‹› If the injectors measure OK, perform the Fuel Injector Balance Test. Refer to Fuel Injector Balance Test (See: Computers and Control
Systems/Testing and Inspection/Component Tests and General Diagnostics/Fuel Injector Balance Test).
‹› If not within the specified range, replace the fuel injector.
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If the ECT sensor is not between 10-32°C (50-90°F), measure and record the resistance of each fuel injector. Subtract the lowest resistance value
from the highest resistance value. The difference between the lowest value and the highest value should be equal to or less than 3 ohm.
‹› If the difference is equal to or less than 3 ohm, perform the Fuel Injector Balance Test. Refer to Fuel Injector Balance Test (See: Computers
and Control Systems/Testing and Inspection/Component Tests and General Diagnostics/Fuel Injector Balance Test).
‹› If the difference is more than 3 ohm, add all of the fuel injector resistance values to obtain a total resistance value. Divide the total resistance
value by the number of fuel injectors to obtain an average resistance value. Subtract the lowest individual fuel injector resistance value from
the average resistance value. Compute the difference between the highest individual fuel injector resistance value and the average resistance
value. Replace the fuel injector that displays the greatest difference above or below the average.
Repair Instructions
Perform the Diagnostic Repair Verification (See: Computers and Control Systems/Testing and Inspection/Diagnostic Trouble Code Tests and
Associated Procedures/Verification Tests and Procedures) after completing the diagnostic procedure.
Fuel Injector Replacement (See: Service and Repair)
