Recently a friend of mine was driving a VW Fox (not new, I'm not sure what year but it was certainly 5+ years old) home in the dark with the lights on. Strangely, after a minute or two of driving all the interior lights turned off. The headlights, and all exterior lights as far as I can tell, remained on. Turning the lights on and off just turned the working exterior lights on and off (still as intended) but the interior lights on the buttons, dash and alike all remained off. This could be dangerous as it became hard to estimate how fast the car was travelling and other important information like fuel, engine temperature and the infamous check engine light. After another few minutes, the headlights went dim temporarily, the other lights all sprang back in to life started working perfectly! The headlights then resumed their normal brightness and they returned home with a perfectly functioning car.
What could be the cause of this? Will it happen again if nothing is changed?
My current thoughts are:
- Probably not alternator problems as headlights are still working and bright as always
- Could be loose wiring or a short circuit
- Some sort of electrical fault (though no EPC or check engine light shown)
- May have poor battery condition so the car is radically trying to reduce consumption so as not to require a jump start on the next drive (though I doubt this somewhat)