P0406 Fault Code Explanation and Causes in Chrysler 300C (AC Misuse Scenario)

During a long road trip, I was using the air conditioning lightly. After exiting a rest stop and accelerating under full power, my daughter requested more cooling. In response, I quickly set the climate control to full heat and turned the fan to maximum — an incorrect adjustment. When warm air began flowing from the vents, I immediately reverted all settings. This is when the Check Engine light activated. I'm wondering if this sudden and aggressive use of the AC system — including high fan speed and extreme temperature settings — could have triggered the P040-6 fault code, which indicates an EGR (Exhaust Gas Recirculation) system issue. The AC has since experienced intermittent failures during the trip: it would get cold but the blower motor would periodically shut off and restart. However, engine performance remained unaffected. The AC now functions normally. Could a sudden temperature shift or freezing within the AC system have caused a temporary glitch in the EGR sensor? My current plan is to reset the fault code and monitor whether it returns under normal driving conditions. If it persists, I'll consider further diagnostics. Thanks for any insights from experienced Chrysler 300C owners!