Fuel Injector Solenoid Coil Test

Fuel Injector Solenoid Coil Test

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (Initial Inspection and Diagnostic Overview) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Initial Inspection and Diagnostic Overview) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Initial Inspection and Diagnostic Overview) provides an overview of each diagnostic category.

Circuit/System Description

The engine control module (ECM) enables the appropriate fuel injector pulse for each cylinder. The ECM supplies a high voltage control circuit and a low control circuit to each of the fuel injectors. The control module controls each fuel injector 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. 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.

Diagnostic Aids

* Monitoring the misfire current counters, or misfire graph, may help to isolate the fuel injector that is causing the condition.
* If the condition is intermittent, move the related harnesses and connectors, with the engine operating, while monitoring the circuit status for the component with a scan tool. The circuit status parameter changes from OK or Indeterminate to Fault if there is a condition with the circuit or a connection.

Reference Information
Schematic Reference

Engine Controls Schematics (Electrical Diagrams)
Electrical Information Reference

* Circuit Testing (Component Tests and General Diagnostics)
* Connector Repairs (Component Tests and General Diagnostics)
* Testing for Intermittent Conditions and Poor Connections (Component Tests and General Diagnostics)
* Wiring Repairs (Component Tests and General Diagnostics)

Component Testing

Note:
* The engine coolant must be within the specified range or mis-diagnosis will occur.
* The resistance test must be performed at the fuel injector or mis-diagnosis will occur.
* The DMM and test leads must be calibrated to 0 ohm in order to prevent mis-diagnosis.

1. Ignition ON, observe the scan tool engine coolant temperature sensor parameter. Verify the parameter is within 10-32°C (50-90°F).

• If not within the specified range, allow the engine to cool, or idle the engine to warm before proceeding.

2. Ignition OFF, disconnect the appropriate multi-way harness connector X110 or X111, at the rear of the intake manifold.
3. Test for 1.3-2.3 ohm between the appropriate fuel injector terminals listed below at the multi-way harness connector.

* Fuel Injector 1 connector X111 terminals 2 and 8.
* Fuel Injector 2 connector X110 terminals 1 and 2.
* Fuel Injector 3 connector X111 terminals 3 and 9.
* Fuel Injector 4 connector X110 terminals 2 and 8.
* Fuel Injector 5 connector X111 terminals 4 and 10.
* Fuel Injector 6 connector X110 terminals 5 and 6.

• If not within the specified range, replace the fuel injector.

Repair Instructions

Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.

Fuel Injector Replacement (Service and Repair)