FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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P0264




DTC P0261, P0262, P0264, P0265, P0267, P0268, P0270, or P0271

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
* Strategy Based Diagnosis Strategy Based Diagnosis
* Diagnostic Procedure Instructions Diagnostic Procedure Instructions

DTC Descriptors
DTC P0261
- Injector 1 Control Circuit Low Voltage

DTC P0262
- Injector 1 Control Circuit High Voltage

DTC P0264
- Injector 2 Control Circuit Low Voltage

DTC P0265
- Injector 2 Control Circuit High Voltage

DTC P0267
- Injector 3 Control Circuit Low Voltage

DTC P0268
- Injector 3 Control Circuit High Voltage

DTC P0270
- Injector 4 Control Circuit Low Voltage

DTC P0271
- Injector 4 Control Circuit High Voltage

Diagnostic Fault Information






Circuit/System Description

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.

Conditions for Running the DTC

* The engine is running.
* The ignition 1 voltage is between 7.5-16 volts.
* The DTCs run continuously once the above conditions are met.

Conditions for Setting the DTC

P0261, P0264, P0267, or P0270

The ECM detects the injector control circuit is open or shorted to ground.

P0262, P0265, P0268, or P0271

The ECM detects the injector control circuit is shorted to voltage.

Action Taken When the DTC Sets

* DTC P0261, P0262, P0264, P0265, P0267, P0268, P0270, P0271 are type B DTCs.
* The ECM commands open loop fuel control.

Conditions for Clearing the DTC

DTC P0261, P0262, P0264, P0265, P0267, P0268, P0270, P0271 are type B DTCs.

Reference Information

Schematic Reference

Engine Controls Schematics (w/Throttle Actuator Controls) Electrical DiagramsEngine Controls Schematics (w/o Throttle Actuator Control) Electrical Diagrams

Connector End View Reference
* Engine Control Module Connector End Views (w/ Throttle Actuator Control) Engine Control Module Connector End Views (w/ Throttle Actuator Control)Engine Control Module Connector End Views (w/o Throttle Actuator Control) Engine Control Module Connector End Views (w/o Throttle Actuator Control)
* Engine Controls Connector End Views (w/ Throttle Actuator Control) Engine Controls Connector End Views (w/ Throttle Actuator Control)Engine Controls Connector End Views (w/o Throttle Actuator Control) Engine Controls Connector End Views (w/o Throttle Actuator Control)

Description and Operation

Fuel System Description Fuel System Description

Electrical Information Reference
* Circuit Testing Circuit Testing
* Connector Repairs Connector Repairs
* Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections
* Wiring Repairs Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference
* Scan Tool Data List (w/ Throttle Actuator Control) Scan Tool Data List (w/ Throttle Actuator Control)Scan Tool Data List (w/o Throttle Actuator Control) Scan Tool Data List (w/o Throttle Actuator Control)
* Scan Tool Data Definitions (w/ Throttle Actuator Control) Scan Tool Data Definitions (w/ Throttle Actuator Control)Scan Tool Data Definitions (w/o Throttle Actuator Control) Scan Tool Data Definitions (w/o Throttle Actuator Control)
* Scan Tool Output Controls (w/ Throttle Actuator Control) Scan Tool Output Controls (w/ Throttle Actuator Control)Scan Tool Output Controls (w/o Throttle Actuator Control) Scan Tool Output Controls (w/o Throttle Actuator Control)

Special Tools Required

J 34730-405 Injector Test Lamp

Circuit/System Verification

Important: If you were sent here from Engine Cranks but Does Not Run, proceed to Circuit/System Testing.


1. Engine running, observe the DTC information with a scan tool. DTC P0261, P0262, P0264, P0265, P0267, P0268, P0270, or P0271 should not set.
2. If the vehicle passes the Circuit/System Verification test, then operate the vehicle within the conditions for running the DTC. You may also operate the vehicle within the conditions that are captured in the Freeze Frame/Failure Records List.

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector of the appropriate fuel injector.
2. Ignition ON, verify that a test lamp illuminates between the ignition 1 voltage circuit and ground.

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.

3. With the ignition OFF, connect a J 34730-405 between the control circuit and the ignition 1 voltage circuit.
4. Engine idling, the test lamp should flash.

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.

5. If all circuits/connections test normal, test or replace the fuel injector.

Component Testing

Important: The engine coolant temperature (ECT) sensor must be between 10-32°C (50-90°F) in order for an accurate measurement.


1. 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.

Repair Instructions

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

* Fuel Injector Replacement Service and Repair
* Control Module References Control Module References for engine control module replacement, setup, and programming