2011 built 130 multijet with cruise control motorhome 9500miles.
After standing for a few weeks over winter, when started engine,
fuel light warning stayed on. Driving off didn't have power, c/c didn't work.
Then within 2 mls c/c came back and engine had normal power.
But warning light stayed on. Then did trip of 370 mls.
Soon after booked appointment for check, had to drive 60 mls.
Then just before arriving going down steep hill on overrun c/c and power cut out. Computer test showed blocked exhaust particle unit, garage tried to regenerate without success. They say I need a new unit $4500 nz.
Test cost $185 nz. So started off home no power or c/c, this went on for about 40 mls. Then I stopped, on restarting c/c and power come back, but the light stayed on of course. I believe a faulty connection or computer.
Any idea's anyone.

see if you can get your own code reader and see what the codes are clear them yourself and see if you can duplicate them i got a launch reader for less than aus$200 and its proved invaluable

Try giving it a good thrash! Sit in 5th with revs high for 30+ miles without stopping. I heard they regenerate themselves by cutting out the egr system at high revs, thus generating high heat in the DPF which burns out the built up crud, if they are driven at low revs on long runs always the regen never happens thus leading to faulty DPF filters
Worth a try