P0403

CIRCUIT DESCRIPTION
The Powertrain Control Module (PCM) monitors the Exhaust Gas Recirculation (EGR) valve pintle position input to ensure that the valve responds properly to commands from the PCM. The linear EGR valve is controlled by using an ignition positive driver and ground circuit within the PCM. The driver has the ability to detect an electrical malfunction in the ignition positive or ground circuit. If an electrical malfunction occurs, the driver signals the PCM to set this DTC.

CONDITIONS FOR RUNNING THE DTC
^ The engine is cranking or running.
^ The system voltage is between 9 and 15 volts.

CONDITIONS FOR SETTING THE DTC
^ The PCM detects an electrical malfunction in the control circuit for the EGR valve.
^ The condition is present for more than 30 seconds.

ACTION TAKEN WHEN THE DTC SETS
^ The PCM illuminates the Malfunction Indicator Lamp on the second consecutive ignition cycle that the diagnostic runs and fails.
^ The PCM records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the PCM stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the PCM records the operating conditions at the time of the failure. The PCM writes the conditions to the Freeze Frame and updates the Failure records.
^ The PCM disables the EGR for the ignition cycle.

CONDITIONS FOR CLEARING THE MIL/DTC
^ The PCM will turn OFF the MIL during the third consecutive trip in which the diagnostic has been run and passed.
^ The History DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.
^ The DTC can be cleared by using a scan tool.

TEST DESCRIPTION

Steps 1-4:

Steps 5-15:

The numbers below refer to the step numbers on the diagnostic table.
4. When using the scan tool to increment the EGR valve, increment the valve to 10 percent then to 0 percent. Repeat this process to see if the test lamp turns ON then OFF. If the test lamp stays ON after commanded to 0 percent the EGR solenoid high control circuit is shorted to voltage.
5. Tests for an open in the ground circuit to the solenoid.
6. Tests if voltage is constantly being applied to the solenoid.