P0403

DTC P0403

CIRCUIT DESCRIPTION
The engine control module (ECM) controls the exhaust gas recirculation (EGR) valve with a solid state device called a driver. The driver supplies the EGR solenoid with 12 volts that is pulse width modulated (PWM) through the EGR solenoid high control circuit. A ground path is provided by the ECM through the EGR solenoid low control circuit. The driver has the ability to detect an electrical malfunction on the EGR solenoid control circuits. If the ECM determines that the driver has detected an electrical malfunction on one of these circuits, DTC P0403 sets.

DTC DESCRIPTOR
This diagnostic procedure supports the following DTC:
DTC P0403 Exhaust Gas Recirculation (EGR) Solenoid Control Circuit

CONDITIONS FOR RUNNING THE DTC
- The engine is cranking or running.
- The Ignition 1 Signal parameter is between 9-18 volts.
- DTC P0403 runs continuously once the above conditions are met.

CONDITIONS FOR SETTING THE DTC
The ECM detects an electrical malfunction in the EGR solenoid high control circuit or the EGR solenoid low control circuit 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.

TEST DESCRIPTION

Step 1 - Step 13:

Step 14 - Step 15:

The number below refers to the step number on the diagnostic table.
6. This step tests for voltage that is constantly being applied to the EGR valve.