Battery
Inspect and clean the battery terminals, check the electrolyte level during scheduled maintenance inspections. The minimum specific gravity should be 1.235. Add distilled water as necessary to maintain the proper water level.
A dead or low battery can be the cause of an ammeter indicating discharge due to lack of initial excitation of the alternator.
Note If the battery was discharged enough that a boost
was needed, the alternator may not recharge the battery. This is because
there may not be adequate current to excite the alternator field.