does your car have the imobaliser...cos i THINK that works by cutting current to the starter..I know on my 940 that i fitted an alarm/imobiliser that low battery voltage is enough to stop the imobaliser relay dea in its tracks (no crank)...connect a booster battery and it fire straight up and it takes no time at all to recharge the booster battery (indicating little charge usage) I am convinnced it voltage related...can i suggest you track the imobliser relay down and pull it and clean the contacts..I believe (AKA know...) that the relay can be pulled and the imobiliser curcuit bypassed with a bridge wire (cars without the imobaliser were, i believe, delivered this way) so it might be worth trying that just to eliminate it..(i do have details on how to do this but obviously it would be irresponsible to post such things in an open forum)