I have approved this post, but moved it to "Help Me Fix My Car" as you do not mention whether you are a Pico User. If you do indeed have a Pico kit and require assistance on diagnosing a fault, I will happily move the thread back to the correct section.
What investigation work have you carried out so far? What model Merc, what engine, what year of manufacture?
What is the number you have quoted? I thought maybe the VIN but I see an "I" which I believe isn't used in VINs?
Also, 16km/hr is around 10mph... isn't that normally the minimum speed cruise can be activated at? Perhaps somehow the signal is inverted, does it work at less than 16km/h, did it work below 16 km/h before?