Battery Health Insights Decoding Tester Fluctuations While Driving

Reason is, your charger might see it as a short (very high amperage load at the onset). Also, check terminal connections for corrosion or lose ... It sounds like your system is operating correctly. You will see charging while driving until the battery is fully charged, then it will gradually taper down to ... So, it kinda sounds like your battery is not being charged during acceleration. Or else, something is drawing more current (dropping the voltage) ... When the batteries need to be charged, the voltage goes up to 14.4v or so, and when it senses they are charged it drops way down, I've seen 12.9 ... This is completely normal with modern charging systems from GM and other manufacturers. Output voltage is computer controlled to provide only what is necessary ... New cars can have an active battery/alternator management system and this behavior as you describe can be completely normal. If not enough current is supplied the voltage drops. Also, low idle RPMs and high load (heaters on, headlights on, and... you get it) might be ... First, check the battery clamps themselves. Have they been over tightened over the years so they are distorted and cannot tightly grip the ... They will intentionally let the battery charge drop while driving - battery voltage will drop to around 12.6v or so when this is occurring. ... battery and alternator, the two most common electrical problems in your car or truck! Check out this playlist for more DIY diagnostics tips ...