P0403 - Exhaust Gas RECIRCULATION (EGR) Control Circuit

WARNING: This page does not describe the selected car, but rather 32 other vehicles, including the 2008 Mercury Sable, 2008 Mercury Mountaineer, 2008 Mercury Milan, 2008 Mercury Mariner, and 2008 Mercury Grand Marquis. However, it is still accessible from the selected car via links, so may be relevant.

P0403 - EXHAUST GAS RECIRCULATION (EGR) CONTROL CIRCUIT

For Vehicles With an Electric EGR (EEGR)
Description:	The EEGR system is continuously monitored to check the 4 EEGR motor coils, circuits, and the powertrain control module (PCM) for opens, shorts to voltage and ground. If a concern is detected, the EEGR system is disabled and additional monitoring is suspended for the remainder of the drive until the next drive cycle.
Possible Causes:	EEGR motor windings open Connector to EEGR not seated Open circuit in the harness from the PCM to the EEGR Short circuit in the EEGR motor Short circuit in the harness from the PCM to the EEGR PCM
Diagnostic Aids:
For All Others
Description:	This test checks the electrical function of the EGR vacuum regulator solenoid. The test fails when the EVR circuit voltage is either too high or too low when compared to the expected voltage range. The EGR system must be enabled for the test to be completed.
Possible Causes:	EVR circuit open EVR circuit short to voltage or ground VPWR open to EGR vacuum regulator solenoid EGR vacuum regulator solenoid PCM
Diagnostic Aids:	The EGR vacuum regulator solenoid resistance is between 26 and 40 ohms.
Application		Key On Engine Off	Key On Engine Running	Continuous Memory
Vehicles with an EGR system module (ESM)		refer to PINPOINT TEST HH .
Vehicles With an Electric EGR (EEGR)		refer to PINPOINT TEST KD .
All others		refer to PINPOINT TEST HE .