Ah IC, I thought he meant a 12v feed/wire to the solenoid from removed battery. I don't know much about the Isuzu, just that the owners are pretty smug about it being the roughest and toughest engine... I suppose it must be, its been 20-30 years now and I rarely hear a complaint about them on this forum . Perhaps that's because the engine isn't a land rover engine and therefore is not bound to the land rover code of conduct where one must report all faults! :p
Anyway its good to know you can easily pull the pin out the bottom of the solenoid on the TDI, I wouldn't have thought of that.

