BMW Repair: electrical problems 88 735i, windshield wipers, driveing

Question
While driveing i noticed my dash lights dimmimg
windshield wipers slowing down and headlights dimming. then engine quit. could this be a bad alternator? if not what else should i look for?

Answer
it could be the alternator. the engine computer needs a certain amount of voltage in order to maintain the engine running. check the charging system by measuring the voltage at the battery terminals with a multimeter with the engine running. turn on some accessories and take a reading. the voltage should be around 13.5 volts, if it is lower, the alternator is no good.