For 1990-2009 cars

### Diagnostic Instructions

• | 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

### DTC Descriptor

DTC P0201: Injector 1 Control Circuit Malfunction
DTC P0202: Injector 2 Control Circuit Malfunction
DTC P0203: Injector 3 Control Circuit Malfunction
DTC P0204: Injector 4 Control Circuit Malfunction
DTC P0205: Injector 5 Control Circuit Malfunction
DTC P0206: Injector 6 Control Circuit Malfunction
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 P0273: Injector 5 Control Circuit Low Voltage
DTC P0274: Injector 5 Control Circuit High Voltage
DTC P0276: Injector 6 Control Circuit Low Voltage
DTC P0277: Injector 6 Control Circuit High Voltage

### Diagnostic Fault Information

Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance
--- | --- | --- | --- | ---
Ignition 1 Voltage | P0201, P0202, P0203, P0204, P0205, P0206 | P0201, P0202, P0203, P0204, P0205, P0206 | -- | --
Injector 1 Control Circuit | P0261 | P0201 | P0262 | --
Injector 2 Control Circuit | P0264 | P0204 | P0265 | --
Injector 3 Control Circuit | P0267 | P0203 | P0268 | --
Injector 4 Control Circuit | P0270 | P0204 | P0271 | --
Injector 5 Control Circuit | P0273 | P0205 | P0274 | --
Injector 6 Control Circuit | P0276 | P0206 | P0277 | --

### Circuit/System Description

The engine control module (ECM) enables the appropriate fuel injector on the intake stroke for each cylinder. Ignition voltage is supplied directly to the fuel injectors. The ECM controls each fuel injector by grounding the control circuit with a solid state device called a driver. The ECM monitors the status of each driver. Each driver has a feedback voltage circuit which the ECM monitors. The injector control circuits are pulled-up to voltage within the ECM . The ECM can determine if a control circuit is open, shorted to ground or shorted to a voltage by monitoring the feedback voltage.

### Conditions for Running the DTC

• | The engine speed is greater than 80 RPM.

• | The ignition voltage is between 10-18 volts.

• | The fuel injector has been commanded ON and OFF at least once.

• | The DTCs run continuously once the above conditions are met.

### Conditions for Setting the DTC

#### DTC P0201, P0202, P0203, P0204, P0205 or P0206

The ECM detects the injector control circuit is open for greater than 4 seconds or for a cumulative of 50 seconds.

#### DTC P0261, P0264, P0267, P0270, P0273 or P0276

The ECM detects the injector control circuit is shorted to ground for greater than 4 seconds or for a cumulative of 50 seconds.

#### DTC P0262, P0265, P0268, P0271, P0274 or P0277

The ECM detects the injector control circuit is shorted to voltage for greater than 4 seconds or for a cumulative of 50 seconds.

### Action Taken When the DTC Sets

DTCs P0201, P0202, P0203, P0204, P0205, P0206, P0261, P0262, P0264, P0265, P0267, P0268, P0270, P0271, P0273, P0274, P0276 and P0277 are type B DTCs.

### Conditions for Clearing the DTC

DTCs P0201, P0202, P0203, P0204, P0205, P0206, P0261, P0262, P0264, P0265, P0267, P0268, P0270, P0271, P0273, P0274, P0276 and P0277 are type B DTCs.

### Diagnostic Aids

• | Performing the fuel injector coil test may help isolate an intermittent condition. Refer to Fuel Injector Solenoid Coil Test .

• | 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 Not Run to Fault if there is a condition with the circuit or a connection.

### Reference Information

#### Schematic Reference

Engine Controls Schematics

#### Connector End View Reference

Component Connector End Views

#### Electrical Information Reference

• | Circuit Testing

• | Connector Repairs

• | Testing for Intermittent Conditions and Poor Connections

• | Wiring Repairs

#### DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

#### Scan Tool Reference

Control Module References for scan tool information

### Circuit/System Verification

1. Observe the scan tool Misfire Current Counters. The Misfire Current Counters should not increment.
2. Engine operating, observe the scan tool DTC information. DTCs P0201, P0202, P0203, P0204, P0205, P0206, P0261, P0262, P0264, P0265, P0267, P0268, P0270, P0271, P0273, P0274, P0276, and P0277 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 are captured in the Freeze Frame/Failure Records Data List.

### Circuit/System Testing

1. Ignition OFF, disconnect the fuel injector multi-way harness connector.

Note: Testing for steps 2 through 4 is performed on the ECM side of the multi-way harness connector.

2. Ignition ON, probe both ignition circuits terminal 1/2 to ground with a test lamp. The test lamp should illuminate at each ignition circuit.

⇒ | If the test lamp does not illuminate, test the ignition circuits for a short to ground, or an open/high resistance. If the circuits test normal and the ignition circuit fuse is open, test or replace the fuel injector.

3. Test for 2.6-4.6 V between the appropriate fuel injector control circuit listed below and ground.

• | Injector 1 terminal 3

• | Injector 2 terminal 6

• | Injector 3 terminal 4

• | Injector 4 terminal 7

• | Injector 5 terminal 5

• | Injector 6 terminal 8

⇒ | If less than the specified range, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the ECM.

⇒ | If greater than the specified range, test the control circuit for a short to voltage. If the circuit tests normal, replace the ECM.

4. Probe the appropriate fuel injector control circuit listed below with a test lamp connected to B+. Engine cranking, verify the test lamp flashes.

• | Injector 1 terminal 3

• | Injector 2 terminal 6

• | Injector 3 terminal 4

• | Injector 4 terminal 7

• | Injector 5 terminal 5

• | Injector 6 terminal 8

⇒ | If the test lamp remains OFF, test the control circuit for a high resistance. If the circuit/connections test normal, replace the ECM.

Note: Testing for steps 5 and 6 is performed on the fuel injector side of the multi-way harness connector. It may be necessary to remove the intake manifold to isolate the condition.

5. Ignition OFF, measure the resistance between the ignition voltage circuit terminal listed below and ground. The DMM should display O.L.

• | Injector 1 terminal 3

• | Injector 2 terminal 6

• | Injector 3 terminal 4

• | Injector 4 terminal 7

• | Injector 5 terminal 5

• | Injector 6 terminal 8

⇒ | If not the specified value, repair the ignition voltage, or control circuit, for a short to ground. If the circuits/connections test normal, test or replace the appropriate fuel injector.

6. Test for 12-16 Ω between the appropriate ignition voltage circuit terminal 1 or 2 and each fuel injector control circuit listed below.

• | Injector 1 terminal 3

• | Injector 2 terminal 6

• | Injector 3 terminal 4

• | Injector 4 terminal 7

• | Injector 5 terminal 5

• | Injector 6 terminal 8

⇒ | If less than the specified range, test for a short between the control circuit and the ignition voltage circuit. If the circuits/connections test normal, test or replace the appropriate fuel injector.

⇒ | If greater than the specified range, test the ignition voltage, and fuel injector control circuit, for an open/high resistance. If the circuits/connections test normal, test or replace the appropriate fuel injector.

### Repair Instructions

Perform the Diagnostic Repair Verification .

• | Fuel Injector and Fuel Rail Replacement

• | Engine Control Module Replacement for engine control module replacement, setup, and programming