Dipped headlamps blowing

[Muchael da silva]

Hi guys,

I have a problem with my Lexus CT200h.

Nearly every month I am replacing the dipped headlight bulbs, they keep blowing.  Yesterday both of them went while I was on the road.  Replaced them this morning, when I checked the filament on the blown bulbs looks like the filament was slightly melted.  This bulb problem has been happening for a while at first I thought it was the way I was installing the bulbs,  but I always wear gloves.  Inspected the wiring can’t see any loose connections.  I’m really puzzled what it can be.  By the way I’m not using bulbs from Lexus, I usually buy Osram H11 bulbs.

 

any help much appreciated.

[Britprius]

It is possible this is a charging system fault. Check the voltage at the Battery with the car in ready mode. It should be about 14.2 volts. Much higher than this will cause the Battery to overcharge, and bulbs to burnout prematurely. This is not an alternator problem as the car does not have one. It has a DC to DC converter to charge the 12 volt Battery from the high voltage "201.6 volts" traction Battery.

If you are using high light output bulbs they do have a much shorter working life, but should last longer than 4 weeks.

John.

[Muchael da silva]

Thanks John I will look into this 

[DanD]

As a matter of interest, did you get to the bottom of this problem?