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 CircuitDTC P0202: Injector 2 Control Circuit
DTC P0203: Injector 3 Control Circuit
DTC P0204: Injector 4 Control Circuit
Diagnostic Fault Information
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
|---|---|---|---|---|
Ignition 1 Voltage - Fuse to Splice | ¹ | ² | -- | -- |
Ignition 1 Voltage - Splice to Injector | ¹ | P0201, P0202, P0203, or P0204 | -- | -- |
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 | -- |
¹Open fuse, cranks no start ²Cranks no start | ||||
Circuit/System Description
The control module enables the appropriate fuel injector pulse for each cylinder. Ignition voltage is supplied 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 more than 11 volts for 5 seconds. |
| • | DTCs P0201-P0204 runs continuously when the above conditions are met. |
Conditions for Setting the DTC
| • | The control module detects an incorrect voltage on the fuel injector control circuit. |
| • | The above condition is met for 0.5 second. |
Action Taken When the DTC Sets
| • | The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails. |
| • | The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records. |
Conditions for Clearing the MIL/DTC
| • | The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail. |
| • | A current DTC, Last Test Failed, clears when the diagnostic runs and passes. |
| • | A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic. |
| • | Clear the MIL and the DTC with a scan tool. |
Diagnostic Aids
Performing the Fuel Injector Diagnosis may help isolate an intermittent condition. Refer to Fuel Injector Diagnosis .
Reference Information
Schematic Reference
Connector End View Reference
Electrical Information Reference
Scan Tool Reference
Special Tools Required
J 44603 Injector Test Lamp
Circuit/System Testing
- Remove the air cleaner outlet duct. Refer to Air Cleaner Outlet Duct Replacement .
- Disconnect the fuel injector.
- With the ignition ON, engine OFF, probe the ignition 1 voltage circuit of the fuel injector with a test lamp that is connected to a good ground. The test lamp should illuminate.
- Connect the J 44603 into the fuel injector connector. Start the engine.
| ⇒ | If the test lamp does not illuminate, repair the open or the high resistance in the ignition 1 voltage circuit. |
| ⇒ | If the test lamp flashes, test for an intermittent or a poor connection at the fuel injector, or a faulty fuel injector. |
| ⇒ | If the test lamp does not flash, test for an open, high resistance, or a short to voltage in the control circuit of the fuel injector, an intermittent or poor connection at the engine control module (ECM). If the circuit tests normal, replace the control module. |
| ⇒ | If the test lamp remains illuminated at all times, test for a short to ground in the control circuit of the fuel injector. If the circuit tests normal, replace the control module. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
