speedo cluster

[cokeman]

I have put some chrome rings in my dash unit CLK 320 2001 model and since replacing it back in the car all the dials work correctly apart from the speed which is reading approx 10 mph wrong eg reads 20mph but actually doing 30mph according to my sat nav has anyone an idea how to set it up again so it is correct or does it need re callibrating at a garage.

 

[television]

I trust you did not remove the pointer to fit the rings

 

[cokeman]

No i didnt remove the pointer

 

[television]

Hard to know what has happened, I would remove it again and just flip the speedo pointer round to check that its not fouling the dial