Service Information

Volt

DTC P0201, P0202, P0203, or P0204

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 P0201: Cylinder 1 Injector Control Circuit

DTC P0202: Cylinder 2 Injector Control Circuit

DTC P0203: Cylinder 3 Injector Control Circuit

DTC P0204: Cylinder 4 Injector Control Circuit

Diagnostic Fault Information

Circuit	Short to Ground	Open/High Resistance	Short to Voltage
Ignition Voltage	P0AB9, P0AC4, P0201, P0202, P0203, P0204, P16E0	P0AB9, P0AC4, P0201, P0202, P0203, P0204, P16E0	-
Fuel Injector 1 Control	P0201, P0300	P0201, P0300	P0201, P0300
Fuel Injector 2 Control	P0202, P0300	P0202, P0300	P0202, P0300
Fuel Injector 3 Control	P0203, P0300	P0203, P0300	P0203, P0300
Fuel Injector 4 Control	P0204, P0300	P0204, P0300	P0204, P0300

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. If the ECM 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 greater than 11 V for greater than 5 s.

•	These DTCs run continuously when the above conditions are met.

Conditions for Setting the DTC

•	The ECM detects an incorrect voltage on the fuel injector control circuit.

•	The above condition is met for greater than 6 s.

•	High resistance in the circuits of the injectors may set a misfire DTC without setting an injector DTC. Test the injector circuits of the affected cylinders for a high resistance if you suspect a condition.

•	Performing the Fuel Injector Solenoid Coil Test may help isolate an intermittent condition.

Reference Information

Schematic Reference

Engine Controls Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

•	Fuel System Description

•	Hybrid Modes of Operation Description

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

Special Tools

J 34730-2C Test Lamp

For equivalent regional tools, refer to Special Tools : Diagnostic Tools .

Circuit/System Verification

Engine running, observe the following control circuit status parameters:

•	Cylinder 1-4 Injector Control Circuit Low Voltage Test Status

•	Cylinder 1-4 Injector Control Circuit Open Test Status

•	Cylinder 1-4 Injector Control Circuit High Voltage Test Status

Each parameter should toggle between OK and Not Run or Not Run and OK.

Observe the DTC information with a scan tool. DTCs P0201, P0202, P0203, or P0204 should not set.
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

Vehicle OFF, disconnect the harness connector at the appropriate Q17 fuel injector.
Vehicle in Service Mode, verify that a test lamp illuminates between the ignition circuit terminal 1 and ground.

⇒	If the test lamp does not illuminate, test the ignition circuit for a short to ground or an open/high resistance. If the circuit tests normal and the ignition circuit fuse is open, test all components connected to the ignition circuit and replace as necessary.

Test for 2.5-3.5 V between the control circuit terminal 2 and ground.

⇒	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 K20 ECM.

⇒	If greater than the specified range, test the control circuit for a short to voltage. If the circuit tests normal, replace the K20 ECM.

Vehicle OFF, connect a J 34730-2C Test Lamp to the Q17 fuel injector harness connector.
Engine running, the test lamp should flash.

⇒	If the test lamp is always ON, test the control circuit for a short to ground. If the circuit tests normal, replace the K20 ECM.

⇒	If the test lamp is always OFF, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K20 ECM.

If all circuits test normal, test or replace the Q17 fuel injector.

Component Testing

•	Fuel Injector Solenoid Coil Test

•	Fuel Injector Balance Test

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

•	Fuel Injector Replacement

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