Been thinking a bit more about this. Find out if the Saab has a 'multitimer' unit, as fitted to Vauxhalls (Saab is a GM company). If this unit fails it can cause these type of problems. It can allegedly be re-set by disconnecting the battery for 30 mins but I've not tried it my self.
Be aware that disconnecting the battery might mean having to reset your security system, immobiliser, keys and radio.
On the Vauxhalls the multitimer is fitted in the fuse box under the drivers side dash.
asf, May 2009
