E53 on board computer problems

[Fletcher]

Hi everyone,

I have a 2006 4.8is, with nav/dsp.
In the last week the dash has gone from miles to kilometres, but temperature is still in Celsius.
On the nav screen I am unable to set the date or time, or change the units. The car is stuck in metric!
The on board computer also doesn’t show range or consumption.
The BC button on the indicator also isn’t showing any info on cluster.

I have used the hidden functions to see that the BC button still works, but I am stumped for the rest!!
I did get another obc but the same issue was there.

Hoping someone here could steer me to a fix?

I am looking to get mileage back on the dash, along with consumption / range etc working on the on board computer.

I’ve uploaded a few pictures.