Mercedes Benz repair: cooling system on Mercedes Benz 190e, mercedez benz, fan clutch

Question
Hi there I have a mercedez benz 190e on 1990 with 137,000 miles on the clock.  When I'm driving the car in summer the temprature builds up to 100 degrees and keeps on rising when in traffic upto 120 degrees before the fan clicks on.  I have noticed that when the temp is betwwen 95-120 degrees the car starts to lack power.  Also once the fan has clicked on the water resovoir tank needs filling up again.  when the vehicle is driving the temp just sits on 80-85 degrees and drives perfect.  Also in winter it takes ages at least 10 miles before the cabin heater gives warm air which after 2 minutes goes cold again. I am definately sure the fan turns on at 120 degrees just under the red overheating mark.  

Answer
Is this a
190E 2.3
or
190E 2.6

120C is excess heat.
Are you in North America?
You need hands on help.
The engine will be wrecked by this issue.

Best guess:
Bad Auxiliary Fan Switch.
Bad radiator.
Bad thermostat.
Bad Fan Clutch.

Vehicle: 1990 Mercedes Benz 190E 2.3
Part: Auxiliary Fan Switch
------------------------------------------------
   Auxiliary Fan Switch
Electro-magnetic
fan clutch
2 pole terminals : color code red : 100 Degrees.    Year: 1988-
Engine: 10-016332-10-036976
------------------------------------------------
   Auxiliary Fan Switch
Electro-magnetic
fan clutch
2 pole terminals : color code red : 100 Degrees.    Year: 1988-
Engine: 12-058478-12-081512
--------------------------------------------------
   Auxiliary Fan Switch
Electro-magnetic
fan clutch
3 pole terminals : color code black : 100 Degrees Auxiliary fan switch.    Engine: 10-036977-
---------------------------------------------
   Auxiliary Fan Switch
Electro-magnetic
fan clutch
3 pole terminals : color code black : 100 Degrees Auxiliary fan switch.    Engine: 12-081513-


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