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 EGR solenoid high control circuit or EGR low control circuit. If an electrical malfunction occurs, the driver signals the PCM to set diagnostic trouble code (DTC) P0403.

CONDITIONS FOR RUNNING THE DTC
^ The engine is cranking or running.
^ The system voltage between 8-18 volts.

CONDITIONS FOR SETTING THE DTC
^ The PCM detects an electrical malfunction in the EGR solenoid high control circuit or in the EGR low control circuit.
^ The condition is present for more than 10 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.
^ Clear the MIL and the DTC with a scan tool.

DIAGNOSTIC AIDS

NOTE:
^ Refer to Connector Test Adapter Kit J 35616-A Notice in Service Precautions.
^ Use the connector test adapter Kit J 35616-A for any test that requires probing the following items:
^ The PCM harness connectors
^ The electrical center fuse/relay cavities
^ The component terminals
^ The component harness connector

Using this kit will prevent damage caused by the improper probing of connector terminals.

If the problem is intermittent, refer to Intermittent Conditions. Intermittent Conditions

TEST DESCRIPTION

Steps 1-2:

Steps 3-15:

The numbers below refer to the step numbers on the diagnostic table.
4. When you use the scan tool in order 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 the lamp is commanded to 0 percent, the EGR solenoid high control circuit is shorted to voltage.
5. This step tests for an open in the ground circuit to the solenoid.
6. This step tests if voltage is constantly being applied to the solenoid.