Just remove the panels under the dashboard in the foot well and feel with you hand up to the instrument cluster and push (and swear and keep some bandages ready for the probable loss of blood)

As for the 190D - I don't think there is a speed sensor. There is for the petrol engines but I'm pretty sure the diesel don't have one.

To avoid speeding tickets use a GPS navigation system / clever telephone (!)

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1992 W201 190E 1.8 171,000 km - Daily driver
1981 W123 300D ~ 100,000 miles / 160,000 km - project car stripped to the bone
1965 Land Rover Series 2a Station Wagon CIS recovery therapy!
1961 Volvo PV544 Bare metal rat rod-ish thing

I'm here to chat about cars and to help others - I'm not here "to always be right" like an internet warrior



Don't leave that there - I'll take it to bits!