• | 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 provide an overview of each diagnostic category. |
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
---|---|---|---|---|
Ignition 1 Voltage | 1 | 2 | -- | -- |
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 | -- |
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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 7.5-16 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 A DTCs. |
• | The ECM commands open loop fuel control. |
DTC P0261, P0262, P0264, P0265, P0267, P0268, P0270, P0271 are Type A DTCs.
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
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 remains ON all the time, test for a short to ground on the control circuit. If circuit/connections test normal, replace the ECM. |
⇒ | If the test lamp remains OFF all the time, test for a short to voltage or an open/high resistance on the control circuit. If circuit/connections test 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.
Measure for 11-14 ohms of resistance between the terminals of the fuel injector.
⇒ | If the resistance is 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 |