Don't know how to totally fix it, but my Serena has a similar, intermittent fault, and the way round the problem is to turn the ignition key VERY SLIGHTLY towards the off position, once the engine is running.
There is a relay in the fuse bank section, that controls all these auxiliary circuits, and whilst it does initially energize when you turn the ignition key to the 'On' position, it drops off when you turn the engine over, and just SLIGHTLY taking the key back towards 'Off' will re-energize the relay. This problem is worse in the winter.
If your auxiliaries never work at all, then it is most probably down to that relay in the fuse bank. Its the one at the bottom I think.
Scratch, May 2011
