P1209

DTC P1209

Circuit Description

The fuel injector control module (FICM) monitors the fuel rail pressure (FRP) sensor voltage, and the fuel rail temperature (FRT) sensor voltage. When the FICM detects a condition with the FRP or FRT sensors, the diagnostic data is communicated to the PCM by a dedicated pulse width modulated (PWM) circuit.

This DTC sets when the FICM diagnostic output PWM signal is not received by the PCM.

Conditions for Running the DTC

The ignition is ON.

Conditions for Setting the DTC

- The FICM diagnostic output PWM signal is not received by the PCM.
- The condition exists for at least 5 seconds.

Action Taken When the DTC Sets

- The control module illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails.
- The control module switches over to gasoline fuel operation.
- 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.

Test Description

The numbers below refer to the step numbers on the diagnostic table.

2. This step determines if the condition is present.
3. If any of the listed DTCs are set, diagnose those DTCs first.
5. This step verifies that the FICM is supplying the correct output voltage. The open circuit voltage should be 5.0 volts.