• | 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. |
Fuel Injector Circuits | Short to Ground | High Resistance | Open | Short to Voltage | Signal Performance |
---|---|---|---|---|---|
Fuel Injector Positive Voltage Control Group 1 | P2146² | P2146 | P0201, P0204¹ | P0201, P0204, P2146 | -- |
Fuel Injector Positive Voltage Control Group 2 | P2149² | P2149 | P0206, P0207¹ | P0206, P0207, P2149 | -- |
Fuel Injector Positive Voltage Control Group 3 | P2152² | P2152 | P0202, P0205¹ | P0202, P0205, P2152 | -- |
Fuel Injector Positive Voltage Control Group 4 | P2155² | P2155 | P0203, P0208¹ | P0203, P0208, P2155 | -- |
Fuel Injector 1 Control | P0201, P0204, P2146 | P2146 | P0201 | P0201 | -- |
Fuel Injector 2 Control | P0202, P0205, P2152 | P2152 | P0202 | P0202 | -- |
Fuel Injector 3 Control | P0203, P0208, P2155 | P2155 | P0203 | P0203 | -- |
Fuel Injector 4 Control | P0201, P0204, P2146 | P2146 | P0204 | P0204 | -- |
Fuel Injector 5 Control | P0202, P0205, P2152 | P2152 | P0205 | P0205 | -- |
Fuel Injector 6 Control | P0206, P0207, P2149 | P2149 | P0206 | P0206 | -- |
Fuel Injector 7 Control | P0206, P0207, P2149 | P2149 | P0207 | P0207 | -- |
Fuel Injector 8 Control | P0203, P0208, P2155 | P2155 | P0208 | P0208 | -- |
¹ Misfire DTCs may also set. ² Injector DTCs may also set. |
The engine control module (ECM) supplies voltage to each fuel injector on the injector positive voltage control circuits. The ECM energizes each fuel injector by grounding the control circuit of that fuel injector. The ECM monitors the status of the injector positive voltage control circuits and the fuel injector control circuits. The injectors are separated into the following four groups:
• | Group 1-DTC P2146 with injectors 1 and 4 |
• | Group 2-DTC P2149 with injectors 6 and 7 |
• | Group 3-DTC P2152 with injectors 2 and 5 |
• | Group 4-DTC P2155 with injectors 3 and 8 |
When a fuel injector circuit condition is detected by the ECM, the affected fuel injectors will be disabled and may disable the affected group of fuel injectors.
• | The engine is running. |
• | The charging system voltage is between 10-18 volts. |
• | The ECM injector output driver detects an incorrect current on a fuel injector circuit. |
• | The condition exists for 1 second. |
• | The control module illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails. |
• | The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Freeze Frame/Failure Records. |
• | The control module disables the group of fuel injectors that have a concern. |
• | 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. |
Important: If you cannot duplicate the condition, operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records.
Observe the DTC information with a scan tool. If DTC P2146, P2149, P2152 or P2155 are set, refer to Diagnostic Trouble Code (DTC) List - Vehicle .
⇒ | If the test lamp illuminates, test the injector control circuit for a short to voltage. |
• | An open between the ignition position voltage control circuit splice and the fuel injector connector |
• | An open between the ECM and the ignition positive voltage control circuit splice |
⇒ | If the circuit does not have a short to voltage or an open, replace the ECM. |
⇒ | If the circuit does not have an open, replace the ECM. |
⇒ | If the resistance is more than 0.2-0.3 ohm resistance, replace the fuel injector. |
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
• | Control Module References for ECM replacement, programing and setup |