s 320 hazzard light flashing

just bought an s320 1994 from private seller yesterday, had a vehicle inspection done , all ok. this morning (after heavy rain all night ) found the hazzard lights flashing. alarm was not going off, car was drivable, alarm reset made no difference, all alarm functions work ok just the hazzards flash continuously, if i press the hazard warning button the flash normaly (slightly slower than they do at the moment) the seller had no idea what it could be, he did have the car preasure washed before i went to buy it, could this be a bit of damp in the electrics. if i remove the fuse to the indicators the alarm still work and indicators still flash so would sudgest is not alarm problem

any thoughts thanks guys and gals