SLC mirror heating issue

I had a similar issue in my SLC. Mirror heating is crucial when the weather turns foul. In my case, it turned out to be a dodgy connection, like a faulty Christmas light. Did you check the voltage at the mirror connector itself with a multimeter? Have you tried wiggling the wires while the heating is switched on to see if it flickers to life? That's a classic test for a loose connection.

Thank you for the response. I have not yet checked the voltage at the mirror connector, nor have I attempted to 'wiggle' the wires while the heating is engaged. Could you elaborate on the specific location of the mirror connector and any precautions I should take when testing the voltage? Also, did you fix it yourself or did you take it to the workshop?

Safety first. Disconnect the battery before poking around with a multimeter. The mirror connector is usually tucked behind the mirror glass itself. You'll need to carefully pry the mirror off; there are plenty of YouTube videos showing how to do this without breaking anything. Once you have access to the connector, check for voltage with the heater switched on. If there's no voltage, the problem is upstream, possibly a fuse or a relay. If there is voltage, then the heater element in the mirror is likely toast. Given the estimated cost of 95€, and depending on your comfort level, I'd just get the workshop to sort it. It's probably less hassle than chasing down a wiring fault.

Based on your recommendation and my own assessment, I have decided to entrust the repair to a qualified Mercedes-Benz technician. They confirmed the defective cable connection, precisely as we suspected. The repair was completed swiftly and efficiently, restoring the mirror heating functionality. The final cost aligned with the initial estimate, ensuring a satisfactory resolution. Thank you again for your time and expertise.