6.1 EGR Control Loop Monitoring: Notes

The EGR control works on an airmass-based control mode in regeneration, and on an EGR-ratio-based control mode outside of regeneration. To prevent the engine from overheating the EGR has to be shut off at a certain engine temperature threshold. (This shut off is also considered by EI-AECD tracking in Scan Tool Mode$1, PID81).

A stuck ECT sensor (above these temperatures) is detected via the comparison of the Fuel Temperature Sensor (FTS) and the ECT during cold start.