Mercedes GLE Blower Motor Issue Resolved

The AUC sensor, or auto recirculation sensor, monitors air quality and controls the HVAC system's fresh air intake. A faulty signal can indeed disable the blower motor in some vehicles. I experienced a similar issue with my Audi A4. Start by thoroughly inspecting the sensor's wiring and connector for any signs of damage, corrosion, or loose connections. A break in the circuit can definitely cause the symptoms you're describing. The BMW AUC is a similar component, but the systems are not cross-compatible.

Where exactly IS this sensor located in the GLE I've been poking around under the hood, but I'm not seeing anything obvious that looks like an odor sensor Is it inside the cabin somewhere, or maybe near the air intake Any tips on what I should be looking for, or how to test the connection once I find it

The AUC sensor is typically located near the fresh air intake, often under the hood, near the windshield, or sometimes integrated into the HVAC unit itself. Given the fault description mentioning a cable or plug connection, I advise a methodical inspection. However, considering your limited experience with HVAC systems, and to avoid potential damage, it may be prudent to consult a qualified technician. The diagnostic fee might be worth preventing further complications. I also recommend checking if there is a TSB Technical Service Bulletin for your specific vehicle related to this issue.

You were spot on I finally found the AUC sensor, and the connector was loose and corroded. Cleaned it up, plugged it back in, and the blower is working again The scanner said the eventual repair cost would have been 95€, I am happy to save that Thanks so much for the help