Hi. I have a year 2000 ducato motorhome which I have owned for 4 months. I can't see any reference to what this grey switch which when turned brings on the red bulb next to the gear stick is for?
Can anyone enlighten me?

Doesn't look like a Fiat switch, so something specific to the motorhome conversion.

Power to charge the auxiliary battery, electric fridge instead of gas, are just my first guesses. See if you can trace the wires behind the switch to see where they go. Or may have to check everything in the back to see what works or not with the switch on or off. If Autotrail are still around, ask them.

Be nice to know.