• | 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. |
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
---|---|---|---|---|
Ignition 1 Voltage - Fuse to Splice | P0201, P0203, P0205, P0207¹ | P0201, P0203, P0205, P0207¹ | -- | -- |
Ignition 1 Voltage - Fuse to Splice | P0202, P0204, P0206, P0208¹ | P0202, P0204, P0206, P0208¹ | -- | -- |
Ignition 1 Voltage - Splice to Injectors | 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 ²Sets individual injector DTC |
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.
• | The engine is running. |
• | The ignition voltage is more than 11 volts for 5 seconds. |
• | DTC P0201-P0208 runs continuously when the above conditions are met. |
• | The control module detects an incorrect voltage on the fuel injector control circuit. |
• | The above condition is met for 1 second. |
• | 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. |
• | 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. |
Performing the Fuel Injector Diagnosis may help isolate an intermittent condition. Refer to Fuel Injector Diagnosis.
Control Module References for scan tool information
J 34730-405 Injector Test Lamp
⇒ | 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 or 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. |
Note: The engine coolant temperature (ECT) sensor must be between 10-32°C (50-90°F) for an accurate measurement.
Measure for 11-14 ohms between the terminals of the injector.
⇒ | If the resistance is not within the specified range, replace the injector. |
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
• | Control Module References for ECM replacement, setup, and programming |