HE71 - DTC 1408: Output Continuous Memory DTCs

Diagnostic Trouble Code (DTC) 1408 indicates that Key On Engine Running (KOER) Self-Test has detected EGR flow out of range.

- EGR valve stuck closed or iced.
- EGR valve diaphragm leaks.
- EGR flow path restricted.
- EGR vacuum hose off, plugged or leaks.
- EVR VPWR circuit open.
- EVR circuit to PCM open.
- EVR circuit to PCM shorted to PWR.
- DPFE sensor pressure hoses both off.
- DPFE sensor pressure hoses reversed.
- DPFE sensor VREF circuit open.
- Downstream pressure hose off.
- Downstream pressure hose plugged.
- Damaged orifice tube assembly.
- Damaged EVR solenoid.
- Damaged DPFE sensor.
- Damaged PCM.

- Output all continuous memory codes.

NOTE: If DTCs other than DTC 1403 or 1406 are output, record codes and refer to Diagnostic Trouble Code Charts after completing this Pinpoint Test. [1][2]Diagnostic Trouble Code (DTC) Charts

- Is DTC 1403 or 1406 output?

YES -- For DTC 1403: GO to HE40. HE40 - DTC 1403: Check For Reversed Pressure Hoses

For DTC 1406: GO to HE60. HE60 - DTC 1406: Inspect Downstream Pressure Hose Connections

NO -- GO to HE72. HE72 - Run KOER Self-Test While Monitoring EGR Vacuum