2005 MY OBD System Operation Summary for Gasoline Engines

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.The differential pressure indicated by the DPFE sensor is also checked at idle with zero requested EGR flow toperform the high flow check. If the differential pressure exceeds a calibratable limit, it indicates a stuck open EGRvalve or debris temporarily lodged under the EGR valve seat (P0402).DPFE EGR Stuck open Check Operation:DTCsMonitor executionMonitor SequenceSensors OKMonitoring DurationP0402once per driving cycleDone after electrical testsCPS, ECT, IAT, MAF, TP10 seconds to register a malfunctionTypical DPFE EGR stuck open check entry conditions:Entry Condition Minimum MaximumEVR dutycycle (EGR commanded off) 0% 0%Engine RPM (after EGR enabled) at idle IdleTypical DPFE EGR stuck open check malfunction thresholds:DPFE sensor voltage at idle versus engine-off signal: > 0.6 voltsJ1979 DPFE EGR Stuck Open Mode $06 DataTest ID Comp ID Description for J1850 Units$45 $20 Delta pressure for stuck open test and threshold voltsConversion for Test ID $45: Multiply by 0.0156 to get A/D counts (0-1024) or 0.0000763 to get voltageMonitor ID Test ID Description for CAN Conventional DPFE Units$31 $84 Delta pressure for stuck open test and threshold kPaFORD MOTOR COMPANY REVISION DATE: APRIL 28, 2004 PAGE 48 OF 131