Hi folks,
I have a 2009 Fit Sport, about 1 month away from the warranty being over. Today when I was at the market, the headlights would not turn on. The obvious thing is to check the fuses. The fuses were fine. I ended up replacing the bulbs and the lights work. So both went out at the same time, I can see that they both blew up as the filament coil is broken. Google searches say that the voltage regulator may be broken and thus too much voltage to the headlights. What are your thoughts on this?

As a side note, I did replace the original bulbs with Philips Extra bright bulbs, but these bulbs have been in the car for almost 3 years now since I bought it. The Philips are regular voltage/wattage bulbs, not those special high wattage ones so they are the same spec as the original OEM bulbs.

Thanks

 

It may be a good idea to check the charging circuit. However, I would think you should have some other electrical issues if you are getting a too high alternator
output or some voltage spikes.

Clifton

 

Fits' headlights don't have a sophisticated regulation circuit (other than what charges the battery) as evidenced by dimming as other accessories turn on/off at idle.

It's normal for transients to occur when a bulb burns out; voltage will have spiked enough to cause the other bulb to burn out almost simultaneously.

The Philips are higher wattage and probably not as robust as the factory halogens.

Put a voltmeter on the battery and see what happens when you flip the lights on/off or the A/C cycles. (don't know what the normal range is, but you should see something around 14 volts with some variation but nothing crazy).