Can A Battery Test Good But Still Be Bad. In the battery is low. A message like this implies that the battery is getting older and not able to charge as efficiently as it used to.
Load Test the Battery. If new it should hold a charge a lot longer. Yes it could test out okay and still have problems.
A battery can still show 12-13volts but have no CCA cold cranking amps which is the power it has to turn the starter.
The proof of a battery is its voltage under load. A voltmeter is the most reliable way to determine if a battery is holding its charge. A good battery should rest at a bit over 12volts and rise to about 135volts on charge. The battery is tested such as load recover and maybe even with a hydrometer and all the results are good.
