Info here, sort of consolidating messages and my experience on this topic. Just got a used 04 XC90 with this bulb failure warning. Like everyone else, I go wtf is a "position light", it's not in the manual. Worse, the manual is dead wrong, in that it incorrectly points to the bumper based light as the fog light, which was not correct when I tested for it, the fog light is in the rear light assembly. That bumper based light is the "position light" and my warning worked correctly. Left one was out, right one was working. OK, no biggee, except I have no reference to the bulb, thanx to the crappy manual. Somehow I deduce that it is the 2825, put one in, nothing, and warning still on. Hmmm. Week passes, I reengage, confirm 2825 is the right bulb, go buy two more. This time, I swap the working bulbs and voila, the light moves to the left. I guess I burned out the new bulb immediately somehow. So I put in two new 2825's as matched pair, and all is well, warning is gone. All this because the manual is wrong, and I burned a bulb immediately somehow. Hope this helps someone.

 

Where did you get the bulbs and was it easy to do?

 

Interesting. For my 2004 XC90 T6 the position lights are the lights in the bumper. I occasionally get this warning light but found that a hard tap on the bumper with my hand fixes the problems. Based on my experience with many Volvos, the biggest consistent problem is the bulb holders. This is the only model I have ever had the problem with.