Quote:
Originally Posted by davesrave
From: https://automedicsafrica.com/cause-o...battery-drain/
PARASITIC DRAIN
If you have your radio presets, security alarms or clocks running after the engine is off, it can drain your battery. The most common causes of parasitic drain are under hood lights, trunk lights, headlights or glove box lights that do not turn off when the door is closed. Relay switches that are stuck in the “on” position can also cause a battery to drain.
FAULTY CHARGING SYSTEM
A faulty or unreliable charging system can also drain the battery while the car is running. When an alternator is not pushing out enough voltage, which should be between 13.5 and 14.5 volts, the battery will drain quickly.
BAD ALTERNATOR DIODE
Alternators with bad diodes can cause battery drain. A bad diode can leak and allow the current to flow in the opposite direction. When this happens, it may keep the charging circuit on after the vehicle engine is shut off, which will cause the battery to drain.
OLD BATTERY
Batteries that are old or have been drained continuously may not hold a full charge anymore. The rule of thumb for replacing a battery is every four to five years. |
the first one was a 'yeah dummy' one for me. now i'm suspecting the bad alternator diode.. that's almost as easy to test as fuses-- just pull the cables off the alternator and let it sit a few days.
a faulty charging system would have driveability issues over the course of a few hours as the battery goes dead, and he said he already replaced the battery, ruling both those out.
Quote:
Originally Posted by humfrz
Say WHAT?
humfrz |
those had generators, right? a lot easier to troubleshoot though!