• | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
• | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
• | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
---|---|---|---|---|
Ignition 1 Voltage | * | ** | -- | -- |
Injector 1 Control Circuit | P0261, P0300 | P0261, P0300 | P0262, P0300 | -- |
Injector 2 Control Circuit | P0264, P0300 | P0264, P0300 | P0265, P0300 | -- |
Injector 3 Control Circuit | P0267, P0300 | P0267, P0300 | P0268, P0300 | -- |
Injector 4 Control Circuit | P0270, P0300 | P0270, P0300 | P0271, P0300 | -- |
* Engine cranks but does not run and the fuse for the injector circuit opens. ** Engine cranks but does not run. |
The engine control module (ECM) enables the appropriate fuel injector pulse for each cylinder. Ignition voltage is supplied to the fuel injectors. The ECM controls each fuel injector by grounding the control circuit via a solid state device called a driver. The ECM monitors the status of each driver.
• | The engine is running. |
• | The ignition 1 voltage is between 11-16 volts. |
• | The DTCs run continuously once the above conditions are met. |
The ECM detects the injector control circuit is open or shorted to ground.
The ECM detects the injector control circuit is shorted to voltage.
• | DTC P0261, P0262, P0264, P0265, P0267, P0268, P0270, P0271 are Type B DTCs. |
• | The ECM commands open loop fuel control. |
DTC P0261, P0262, P0264, P0265, P0267, P0268, P0270, P0271 are Type B DTCs.
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Control Module References for scan tool information
J 34730-405 Injector Test Lamp
Important: If you were sent here from Engine Cranks but Does Not Run, proceed to Circuit/System Testing.
⇒ | If the test lamp does not illuminate, repair the ignition 1 voltage circuit for a short to ground or an open/high resistance. Replace the fuse if necessary. |
⇒ | If the test lamp is always ON, test the control circuit for a short to ground. If circuit tests normal, replace the ECM. |
⇒ | If the test lamp is always OFF, test the control circuit for a short to voltage or an open/high resistance. If circuit tests normal, replace the ECM. |
Important: The engine coolant temperature (ECT) sensor must be between 10-32°C (50-90°F) in order for an accurate measurement.
⇒ | If not within the specified range, replace the fuel injector. |
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
• | Control Module References for ECM replacement, setup, and programming |