The battery light coming on means the operating voltage is below a proper amount. This is caused by most commonly a drained battery or a failing alternator. The other possible causes are a slipping drive belt caused by a weak tensioner or a faulty regulator.
This system uses what is called an Electronic Voltage Regulator which is a software program in the PCM that compares the voltage feed it gets from the alternator and it compares the voltage signal it gets from the TIPM. Here is the info about this system that gives more detail. However, this means we need to connect a scan tool to the vehicle and monitor what the TIPM has for voltage and what the PCM sees for voltage. If they don't match then we need to replace that component that doesn't match the actual voltage from the alternator. It will turn the light on if these numbers are not the same.
Also, we need to check for codes because when this light goes on it should set a DTC as well. Most likely it will be stored but it should be there. Here is a guide that will help with that:
https://www.2carpros.com/articles/checking-a-service-engine-soon-or-check-engine-light-on-or-flashing
Please let me know if you have questions and we can go from there. Once you run through this info, please let me know what you find. Thanks
Apr 20, 2020 at 6:15 PM
