Date registered: Feb 2010
Vehicle: 1972 280SEL daily driver. 904 Dark Blue with cognac interior. euro 4.5 engine
Location: Williamsburg, VA
Mentioned: 3 Post(s)
Quoted: 36 Post(s)
Hard to say by just looking at a photo. The switch works almost like the original but without the infinite speed control. There should be one 12v input to the switch. There are two output contacts. One puts out 0 or 12v (does not go through the resistors) and it should jump over to the temperature knob. This is power to the clutch. The other output comes from the resistors. At high speed it should be 12v and then progressively less for lower speeds. This contact powers the blower.
I don't remember what colors go where and I would have to look at the switch to see which contact is which. If you have a volt meter that also measures resistance, it should be easy to figure out.