So i have a 1993 w124 400e and everytime i shut off the car the radio and windows all work stil, and after about lik 15 minutes it will all not work, but when i unplug radio all the power would go off, and if i put it back in it all the power would work, let me remind you ther is no key in the ignition and the SRS light will go on when i unplug and plug the radio... it will be alot of help if someonme knows what is wrong with it..