Mercedes Repair Questions? Ask a Mechanic for Answers ASAP
hello, The fan has a speed regulator relay installed in the ventilation box. It receives the speed comand from the AC control unit and then adjusts the current to the fan. Please have it's voltage supply checked. Usually this regulator fails.
It will be next week before I can take it to the garage to try it. I'll let you know!
No problem, please reply whenever it is most convenient for you.