12V Battery Causing Cascade Faults
ModerateElectrics & ElectronicsThe 12V auxiliary battery degrades prematurely, triggering multiple seemingly unrelated high-voltage system errors. A failing 12V battery can make the car refuse to start or enter a fault state.
Multiple warning lights, Car won't start, "Electrical system fault" message, Infotainment resets
- Test 12V battery voltage (should be 12.4V+)
- Check service history for 12V battery replacement