These are the instructions on how to change the evaporator temperature sensor from Mercedes-Benz workshop information system. The part cost me GBP25 (about $40 at the present rate of exchange). It looks very easy. I have attached a diagram, too.
Cover on bottom section below left of instrument panel
remove.
2-pin plug connection
disconnect.
Evaporator temperature sensor (B10/6)
withdraw.
Temperature sensor
test, renew if necessary.
Install
in reverse order.