P0201

CIRCUIT DESCRIPTION
The Powertrain Control Module (PCM) enables the appropriate fuel injector on the intake stroke for each cylinder. A voltage is supplied directly to the fuel injectors. The PCM controls each fuel injector by grounding the control circuit via a solid state device called a driver. The PCM monitors the status of each driver. If the PCM detects an incorrect voltage for the commanded state of the driver, a fuel injector control Diagnostic Trouble Code (DTC) sets.

CONDITIONS FOR RUNNING THE DTC
^ The engine is running.
^ The ignition voltage is between 9-18 volts.

CONDITIONS FOR SETTING THE DTC
^ The PCM detects an incorrect voltage on the fuel injector control circuit.
^ The condition exists for 30 seconds.

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.
^ Use a scan tool in order to clear the MIL and the DTC.

DIAGNOSTIC AIDS
^ Performing the Fuel Injector Coil test may help isolate an intermittent condition. Refer to Fuel Injector Coil Test. Component Tests and General Diagnostics
^ If the condition is intermittent, refer to Intermittent Conditions. Intermittent Conditions

TEST DESCRIPTION

Steps 1-11:

Steps 12-19:

The numbers below refer to the step numbers on the diagnostic table.
2. The misfire current counters may not increment if certain DTCs are set. Use a scan tool to clear the DTCs. Monitoring the misfire current counters isolates which fuel injector is not operating. A cylinder that is misfiring can also cause the misfire current counters to increment for another cylinder. Diagnose the cylinder with the highest level of misfire first.
4. This step isolates the condition. If the test lamp blinks, the PCM is providing ground to the fuel injector.
5. This step tests if a ground is constantly being applied to the fuel injector.
6. This step isolates the circuit between the multi-way connector and the PCM. An open or short to voltage on the fuel injector control circuit will not allow the test lamp to blink.
8. This step inspects for fuel injector harness damage between the multi-way connector and the upper intake manifold. Careful inspection may isolate the condition before removal of the upper intake manifold.
10. Perform the continuity test at the multi-way connector. If the DMM displays OL test the circuits for an open or a poor connection.
13. This step isolates the circuit between the multi-way connector and the fuel injector. A short to voltage on the fuel injector control circuit will set this DTC.