2002 MY OBD-II System Operation Summary - MotorCraftService.com

The Delta Pressure Feedback EGR Monitor is a series of electrical tests and functional tests that monitor variousaspects of EGR system operation.First, the Delta Pressure Feedback EGR (DPFE) sensor input circuit is checked for out of range values (P1400P1401). The Electronic Vacuum Regulator (EVR) output circuit is checked for opens and shorts (P1409).EGR Electrical Check Operation:DTCsMonitor executionMonitor SequenceSensors OKMonitoring DurationP1400, P1401, P1409Continuous, during EGR monitorNone4 seconds to register a malfunctionTypical EGR electrical check entry conditions:EGR system enabledTypical EGR electrical check malfunction thresholds:DPFE sensor outside voltage: > 4.96 volts, < 0.195 voltsEVR solenoid smart driver status indicates open/shortNote: EGR normally has large amounts of water vapor that are the result of the engine combustion process. Duringcold ambient temperatures, under some circumstances, water vapor can freeze in the DPFE sensor, hoses, aswell as other components in the EGR system. In order to prevent MIL illumination for temporary freezing, thefollowing logic is used:If an EGR system malfunction is detected above 32 o F, the EGR system and the EGR monitor is disabled for thecurrent driving cycle. A DTC is stored and the MIL is illuminated if the malfunction has been detected on twoconsecutive driving cycles.If an EGR system malfunction is detected below 32 o F, only the EGR system is disabled for the current drivingcycle. A DTC is not stored and the I/M readiness status for the EGR monitor will not change. The EGR monitor,however, will continue to operate. If the EGR monitor determined that the malfunction is no longer present (i.e., theice melts), the EGR system will be enabled and normal system operation will be restored.FORD MOTOR COMPANY REVISION DATE: OCTOBER 02, 2001 PAGE 30 OF 66