Circuit 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 control module detects an incorrect voltage for the commanded state of the driver, a diagnostic trouble code (DTC) will set.
DTC Descriptor
This diagnostic procedure supports the following DTCs:
| • | DTC P0262 Injector 1 Control Circuit High Voltage |
| • | DTC P0265 Injector 2 Control Circuit High Voltage |
| • | DTC P0268 Injector 3 Control Circuit High Voltage |
Conditions for Running the DTC
| • | The engine is running. |
| • | This DTC runs continuously once the above conditions are met. |
Conditions for Setting the DTC
The control module detects a short to voltage on the fuel injector control circuit.
Action Taken When the DTC Sets
| • | 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. |
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 Coil Test may help isolate an intermittent condition, refer to Fuel Injector Solenoid Coil Test . |
| • | For an intermittent condition, refer to Intermittent Conditions . |
Step | Action | Yes | No |
|---|---|---|---|
Schematic Reference: Engine Controls Schematics Engine Controls schematics Connect End View Reference: Engine Control Module Connector End Views Engine Control Module (ECM) Connector End Views or Engine Controls Connector End Views Engine Controls Connector End Views | |||
1 | Did you perform the Diagnostic System Check - Engine Controls? | Go to Step 2 | |
2 |
Does DTC P0262, P0265, or P0268 set? | Go to Step 4 | Go to Step 3 |
3 |
Did the DTC fail this ignition? | Go to Step 4 | Go to Diagnostic Aids |
4 |
Does the test lamp turn ON and OFF? | Go to Step 6 | Go to Step 5 |
5 | Test the control circuit of the fuel injector for a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 10 | Go to Step 7 |
6 | Test for shorted terminals and poor connections at the fuel injector. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 10 | Go to Step 8 |
7 | Test for shorted terminals and poor connections at the engine control module (ECM). Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 10 | Go to Step 9 |
8 | Replace the affected fuel injector. Refer to Fuel Injector Replacement . Did you complete the replacement? | Go to Step 10 | -- |
9 | Replace the ECM. Refer to Engine Control Module Replacement . Did you complete the replacement? | Go to Step 10 | -- |
10 |
Did the DTC fail this ignition? | Go to Step 2 | Go to Step 11 |
11 | Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed? | System OK | |
