Likely causes, most common first
Snapped or slipping accessory belt
Often comes with an overheat warning too.
Corroded main charging cable
Voltage drop test finds it in minutes.
Checks to run first
- 1.Measure voltage at idle: healthy is 13.8–14.6V
- 2.Check the serpentine belt visually
- 3.Head for a workshop, not home — you have limited range
Frequently asked questions
- battery light on but car still running?
- The battery light is a charging-system light. The car is running on stored battery power and will stall once it is empty.
- Is it safe to drive with this?
- No. This symptom can leave you stranded or cause much more expensive damage — get it looked at before driving further.
- How much does it cost to fix?
- The most likely repair is alternator replacement, which runs $265–$1,310 in the US including labour, or $150–$650 in parts if you fit it yourself.
Electrical & sensors parts
Batteries, alternators, starters, sensors and wiring
Find parts that fit
Year, make, model, trim — then only parts that fit your car.