Eingeschickt von Patrick auf roadfly:
just changed out the cable between alternator and the B+ post. After 17 years of cooking above the exhaust manifold the insulation has developed many cracks and this spot in the photo already shows copper corrosion (was inside the metal conduit). Corrosion like that can leak current and be responsible for low charging voltage and of course battery run down. The new cable is made from much better insulation material and I route it outside the conduit (less heat and easy inspection in the future).
Wenn Ihr also sehr niedrige Volt habt, muss es nicht unbedingt an Batterie oder Lima liegen.