How does the fridge turn on ■■?
I’m desperate for a cuppa tea… but I want the fridge on to keep the milk in 
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There are various fridge options - even for the Actros.
Normally, if you fully open the drawer, the thermostat & on/off switch is revealed.
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There should b on/off switch left side of steering wheel, with snow flake like sinbol and red diod when turned on. There was same button with slightly different sinbol in the old shape merc, but that was for activating the “aircon” like thingy… 
Hope you find it and enjoy nice cuppa in the meantime.
Made my first post. 
hello everyone!
Jan 
As above pointed out except they missed 1 important bit that separates it from the air con switch.
It’s a snowflake inside a square - the square representing a fridge I guess??
Make sure that is turned on, it’s on the dash normally as mentioned above, although all switches are moveable now on the Actros since it uses data signals and not direct wiring 
Happy days …Cheers lads !!!
I thought it was the aircon switch 