Wierd electrical situation

[Dash01]

With engine off and key removed and all switches off, the dashboard lights with the mileage indication showing. This is running the battery down.

No other indications, just the odometer readout.

Why, and how to fix?

[shogun]

I had this once and found out that the battery was low. Recharged it and it never appeared again.
Apparently the system got confused by too low battery.
Check the battery voltage.