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 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 P0205: Injector 5 Control Circuit
DTC P0206: Injector 6 Control Circuit
DTC P0207: Injector 7 Control Circuit
DTC P0208: Injector 8 Control Circuit

### Diagnostic Fault Information

Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance
--- | --- | --- | --- | ---
Ignition 1 Voltage - Fuse to Splice Pack | P0201 P0203 P0205 P0207¹ | P0201 P0203 P0205 P0207¹ | -- | --
Ignition 1 Voltage - Fuse to Splice Pack | P0202 P0204 P0206 P0208¹ | P0202 P0204 P0206 P0208¹ | -- | --
Ignition 1 Voltage - Splice Pack to Connectors | ¹, ² | ² | -- | --
Fuel Injector 1 Control | P0201 | P0201 | P0201 | --
Fuel Injector 2 Control | P0202 | P0202 | P0202 | --
Fuel Injector 3 Control | P0203 | P0203 | P0203 | --
Fuel Injector 4 Control | P0204 | P0204 | P0204 | --
Fuel Injector 5 Control | P0205 | P0205 | P0205 | --
Fuel Injector 6 Control | P0206 | P0206 | P0206 | --
Fuel Injector 7 Control | P0207 | P0207 | P0207 | --
Fuel Injector 8 Control | P0208 | P0208 | P0208 | --
¹Open Fuse ²Set Individual Injector DTC

### Circuit Description

The control module enables the appropriate fuel injector pulse for each cylinder. Ignition voltage supplies to the fuel injectors. The control module controls each fuel injector by grounding the control circuit via a solid state device called a driver. The control module monitors the status of each driver. If the control module detects an incorrect voltage for the commanded state of the driver, a fuel injector control circuit DTC sets.

### Conditions for Running the DTC

• | The engine is running.

• | The ignition voltage is between 9-18 volts for 1 second.

• | DTC P0201-P0208 runs continuously.

### Conditions for Setting the DTC

• | The ECM detects that the commanded state of the injector control circuit does not match the actual state.

• | It occurs at least 20 times during the 25 tests.

### Action Taken When the DTC Sets

DTC P0201-P0208 are Type B DTCs.

### Conditions for Clearing the DTC

DTC P0201-P0208 are Type B DTCs.

### Diagnostic Aids

Performing the Fuel Injector Diagnosis may help find an intermittent location. Refer to Fuel Injector Diagnosis.

### 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

Diagnostic Trouble Code (DTC) Type Definitions

#### Scan Tool Reference

• | Scan Tool Data List

• | Scan Tool Data Definitions

• | Engine Control Module Scan Tool Information

#### Special Tools

J 34730-405 Injector Test Lamp

### Circuit/System Verification

With the engine running, observe the scan tool cylinder injector circuit status parameter. The parameter should display OK.

### Circuit/System Testing

1. Remove the engine sight shield.
2. Ignition OFF, disconnect the affected fuel injector harness connector at the fuel injector.
3. Ignition ON, verify that the test lamp illuminates between the ignition 1 voltage circuit terminal A and ground.

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

⇒ | If the test lamp does not illuminate, test the ignition 1 circuit for a short to ground, an open or high resistance.

4. Connect the J 34730-405 between the control circuit terminal B and the ignition 1 voltage circuit terminal A. Start the engine.

⇒ | If the test lamp flashes, replace the fuel injector.

⇒ | If the test lamp does not flash, test the control circuit of the fuel injector for an open, high resistance, or a short to voltage. If the circuit test normal, replace the ECM.

⇒ | If the test lamp remains illuminated, test the control circuit of the fuel injector for a short to ground. If the circuit test normal, replace the ECM.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

• | Fuel Injector and Fuel Rail Replacement

• | Control Module References for ECM replacement, setup, and programming