headlight bulbs go out repeatedly

[E Showell]

My belief is that there was a factory recall for the bulb issue that was solved by Volvo adding an additional length of wire to increase resistance, as noted by mecheng, and prolong bulb life. I have that part on one of my cars and, if the label is still legible, I could probably read off the part number and post if you think it would be helpful. Might be a day or so before I can get to it, however.

[erikv11]

Evan's report is spot on. Volvo put the extra harness wire in at each headlamp due to customer complaints about short bulb life. The part number is 9162343.

[abscate]

There is a intermediate wire on my S70 that adds resistance to lengthen the build life. I bypassed it in the winter when its dark, I may add it back in the summer when its bright out. Also, heat is the enemy of the bulb.

FWIW, I always unplug these wires right away when I get a new P80, and I don't have issues with bulb longevity.

I did the same on my P80

I also turn off the DRLs, and don't drive at night much either.

[MadeInJapan]

I got a check for like $10 a few years ago- part of a class action on early dying bulbs so it's not just a Bolvo issue.