Why does the indicator light not change after a new battery is fully charged?

[DerekDella]

New battery indicator light not changing after full charge may be caused by battery water shortage. Below is an introduction to automotive battery knowledge: 1. Introduction: Automotive battery, also called storage battery, is a type of battery that works by converting chemical energy into electrical energy. Typically, what people refer to as batteries are lead-acid batteries. That is, a battery mainly made of lead and its oxides, with sulfuric acid solution as the electrolyte. 2. Ordinary battery: The plates of an ordinary battery are composed of lead and lead oxides, with an aqueous solution of sulfuric acid as the electrolyte. Its main advantages are stable voltage and low cost; the disadvantages are low specific energy (i.e., the electrical energy stored per kilogram of battery), short service life, and frequent daily maintenance.

[NovaRose]

I just encountered a similar issue - the indicator light won't turn off after fully charging a new battery, which is really frustrating. As a long-time car enthusiast, I believe we should start by checking the charger and connection cables. Sometimes a new battery might appear fine on the surface, but an aging charger or incorrect settings can cause indicator light malfunctions. I've tried measuring the charger's output voltage with a multimeter - it should normally be around 14V. If it's too low or too high, the light won't turn off. Additionally, loose or oxidized connection cables are common problems, as poor contact prevents signals from reaching the indicator light. For DIY troubleshooting, first disconnect the charger and clean the electrodes before trying again. If that doesn't work, try using a different charger. The new battery might also have internal issues, such as a factory defect like a short circuit - in such cases, I recommend contacting the seller for warranty inspection. Remember, delaying repairs might damage the battery, so timely action is the wisest approach.

[LaDonovan]

I just replaced my new battery, and the charging light wouldn't turn off, which really worried me at the time. As an average car owner, recalling my experience, I first checked if the charger's power plug was securely connected, then inspected the electrodes for rust or looseness. Poor contact can cause unstable current, preventing the light from changing. I also measured the voltage—a simple multimeter will do—a fully charged battery should read 12.6V or higher. Otherwise, the charger might be faulty or the new battery could have internal defects. In my case, I found the charger's fan was stuck, causing overheating, and replacing it fixed the issue. I recommend not trying to force a solution yourself; instead, visit a professional shop for diagnostics—they can quickly pinpoint the problem. Also, keep the new battery in a dry charging environment to avoid short circuits and extend its lifespan. Early detection and resolution can save you more repair costs later.

[DelEsther]

The charging light remains on after the new battery is fully charged, commonly due to issues in the charging circuit or indicator system. When analyzing, I considered the principle: the charger detects voltage via sensors and automatically cuts off power to turn off the light when fully charged. However, if the sensor malfunctions or the circuit is broken, the light won't respond. For example, loose connections on the new battery terminals can cause signal loss, or internal protection failure in the charger may lead to continuous power supply without indicating completion. A simple check involves using a multi-port tester to verify if the voltage meets the standard 12.6V. If abnormal, it could indicate a factory defect in the new battery or external factors. Replace the charging equipment early to prevent damage. This way, minor issues can be prevented from escalating into major problems.