Hi all, i just purchased a 91 525I from a friend of mine who bought the car new. he has all the receipts from day one for service. The car as 105k with a rebuilt tranny put in about 10k. The problem is there is no sound from the stereo, everything lights up and I can put the code in but no sound. He did let the battery die over the winter and there is mice damage on the insulation under the hood. All the fuses are fine but I have not pulled the radio.