Offroad-Express

this afternoon my truck has done something very odd!
Relevant information - was towing a big, full trailer that was emptied and while empty reversing down a long drive with the reverse beeper going for it. then it did a beep out of time then just stopped....

I have checked all the fuses. twice - in cab and under hood.

now when you start the truck no warning lights come on - apart from the battery signal, the entire dash doesnt work but the backlight (when lights are on) and indicators do.
The auto gear selector doesnt work unless manual override is used, gearbox holds on to gears a lot longer and changes roughly.
the heater/fan unit doesnt work/have power.
the windows dont work apart from the rear window.

I have no idea at all! could anyone please shed some light on the situation?

Thanks
Chris

just had a rough look through some wiring diagrams, i would suspect ignition switch. check what voltage you have coming out on both ignition connections.