I don't know whether this is helpful or leading you up the garden path; Firstly my old bus is a 2007 Diesel GV. Today whilst picking up some items from the local electrical wholesaler the GV wouldn't start - not unusual so gave her a burst of Quickstart and brum brum but after a couple of miles I noticed the voltage reading (have a cheap & very useful voltmeter plugged into the cig. socket) was 11.3 (this is whilst driving whereas it's normally around the 12.9 to 13.3 ish; as I continued the voltage dropped quicker than the fuel gauge down to around 11.1 and then the gearbox decided to go into limp mode i.e. it wouldn't change up. After a couple of miles dash lights started lighting up at random, then the speedo died shortly after followed by the tacho, shortly after and 800 yards from home the engine followed suit - amazing how heavy the steering is without the servo helping out. I have never had an electrical problem with the car before (lots of starting issues)... Don't know what's wrong yet will get the fluke out tomorrow and investigate but to summarise low voltage does appear to restrict your choice of gears to 1.
