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P0271




DTC P0201-P0204, P0261, P0262, P0264, P0265, P0267, P0268, P0270, P0271, P2146, P2149, P2152, or P2155

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.

DTC Descriptors
DTC P0201
- Injector 1 Control Circuit

DTC P0202
- Injector 2 Control Circuit

DTC P0203
- Injector 3 Control Circuit

DTC P0204
- Injector 4 Control Circuit

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

DTC P2146
- Injector Positive Voltage Control Circuit Group 1

DTC P2149
- Injector Positive Voltage Control Circuit Group 2

DTC P2152
- Injector Positive Voltage Control Circuit Group 3

DTC P2155
- Injector Positive Voltage Control Circuit Group 4

Diagnostic Fault Information





Circuit/System Description

The engine control module (ECM) supplies voltage to each fuel injector on the injector high voltage supply circuits. The ECM energizes each fuel injector by grounding the high voltage control circuit of that fuel injector. The ECM monitors the status of the injector high voltage supply circuits and the fuel injector high voltage control circuits. When a fuel injector circuit condition is detected by the ECM, the affected fuel injector will be disabled.

Conditions for Running the DTC

* The engine speed is greater than 80 RPM.
* The ignition 1 signal parameter is between 8-18.1 volts.
* The DTCs run continuously within the enabling conditions.

Conditions for Setting the DTC

The control module detects an incorrect voltage on the high voltage supply circuit or the high voltage control circuit for greater than 4 seconds continuously or 50 seconds cumulative.

Action Taken When the DTC Sets

DTCs P0201, P0202, P0203, P0204, P0261, P0262, P0264, P0265, P0267, P0268, P0270, P0271, P2146, P2149, P2152, and P2155 are Type B DTCs.

Conditions for Clearing the DTC

DTCs P0201, P0202, P0203, P0204, P0261, P0262, P0264, P0265, P0267, P0268, P0270, P0271, P2146, P2149, P2152, and P2155 are Type B DTCs.

Reference Information
Schematic Reference

Engine Controls Schematics (Electrical Diagrams)
Connector End View Reference

* Component Connector End Views (Connector Views)
* Inline Harness Connector End Views (Connector Views)

Description and Operation

Fuel System Description (Fuel System Description)
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)

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions (Diagnostic Trouble Code Descriptions)
Scan Tool Reference

Control Module References (Programming and Relearning) for scan tool information

Circuit/System Verification

1. Observe the Misfire Current Counters with a scan tool. The Misfire Current Counters should not be incrementing.
2. Engine operating, observe the DTC information with a scan tool. DTCs P0201, P0202, P0203, P0204, P0261, P0262, P0264, P0265, P0267, P0268, P0270, P0271, P2146, P2149, P2152, and P2155 should not set.
3. Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

Circuit/System Testing

1. Ignition OFF, disconnect the X162 fuel injector multi-way harness connector.
2. Inspect the X162 fuel injector multi-way harness connector for proper connection, proper terminal contact, and proper terminal retention force.

• If a condition is found, repair the poor connection at the X162 connector.

3. Engine cranking, verify that a test lamp flashes brightly between ground and the high voltage supply circuit terminal, ECM side of the connector, of the appropriate fuel injector listed below.

* Injector 1 terminal 7
* Injector 2 terminal 8
* Injector 3 terminal 9
* Injector 4 terminal 10

• If the test lamp is always ON, test the appropriate fuel injector high voltage supply circuit for a short to voltage. If the circuit tests normal, replace the ECM.
• If the test lamp is always OFF, test the appropriate fuel injector high voltage supply circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the ECM.

4. Engine cranking, verify that a test lamp flashes dimly between B+ and the high voltage control circuit terminal, ECM side of the connector, of the appropriate fuel injector listed below.

* Injector 1 terminal 1
* Injector 2 terminal 2
* Injector 3 terminal 3
* Injector 4 terminal 4

• If the test lamp is always ON, test the appropriate fuel injector high voltage control circuit for a short to ground. If the circuit tests normal, replace the ECM.
• If the test lamp is always OFF, test the appropriate fuel injector high voltage control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the ECM.

5. Ignition OFF, test for continuity between the suspected high voltage supply circuit and the remaining high voltage supply circuits, engine side of the connector. The DMM should display OL.

* Injector 1 terminal 7
* Injector 2 terminal 8
* Injector 3 terminal 9
* Injector 4 terminal 10

• If less than the specified value, repair the high voltage supply circuit for a short to the high voltage supply circuit.

6. Ignition OFF, verify that a test lamp does not illuminate between the appropriate high voltage supply circuit terminal listed below, engine side of the connector, and B+.

* Injector 1 terminal 7
* Injector 2 terminal 8
* Injector 3 terminal 9
* Injector 4 terminal 10

• If the test lamp illuminates, repair the high voltage supply circuit for a short to ground.

7. Ignition OFF, test for continuity between the suspected high voltage control circuit and the high voltage supply circuits listed below, engine side of the connector. The DMM should display OL.

* Injector 1 terminal 7
* Injector 2 terminal 8
* Injector 3 terminal 9
* Injector 4 terminal 10

• If less than the specified value, repair the high voltage control circuit for a short to the high voltage supply circuit.

8. Ignition OFF, verify that a test lamp does not illuminate between the appropriate high voltage control circuit terminal listed below, engine side of the connector, and B+.

* Injector 1 terminal 1
* Injector 2 terminal 2
* Injector 3 terminal 3
* Injector 4 terminal 4

• If the test lamp illuminates, repair the high voltage control circuit for a short to ground.

9. Ignition OFF, test for 1.5-4 ohms of resistance between the appropriate fuel injector high voltage supply circuit terminal and the fuel injector high voltage control circuit terminal, engine side of the connector, of the appropriate fuel injector listed below.

* Injector 1 terminals 1 and 7
* Injector 2 terminals 2 and 8
* Injector 3 terminals 3 and 9
* Injector 4 terminals 4 and 10

• If the resistance is not within the specified range, test for an open/high resistance between X162 and the appropriate fuel injector harness connector. If the circuits test normal, test or replace the fuel injector.

Component Testing

Verify the resistance of each fuel injector with one of the following methods:

* If the engine coolant temperature (ECT) sensor is between 10-32°C (50-90°F), the resistance of each fuel injector should be 1.25-1.75 ohms.

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

* If the ECT sensor is not between 10-32°C (50-90°F), measure and record the resistance of each fuel injector with a DMM. 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 0.45 ohms.

• If the difference is more than 0.45 ohms, 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 (Verification Tests) after completing the diagnostic procedure.

* Direct Fuel Injector Replacement (Service and Repair)
* Sumitomo Connectors (Component Tests and General Diagnostics)
* Control Module References (Programming and Relearning) for ECM replacement, setup, and programming

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