12V Battery Failure
ModerateElectrics & ElectronicsThe 12V auxiliary battery degrades faster than expected, triggering a cascade of seemingly unrelated high-voltage system errors. A weak 12V battery can prevent the car from starting entirely.
Typical symptoms
- •Multiple unrelated warning lights
- •Car won't start
- •"Electrical system malfunction"
- •Infotainment resets randomly
What to inspect before you buy
- ✓Test 12V battery voltage
- ✓Check service history for replacement
- ✓Look for recent 12V battery fault codes