That's what happens (color shift) when an HID bulb is burning out. This happens before the bulb actually burns out, unlike a halogen bulb that dims over time and then goes out (or just goes out unexpectedly).

Time for new bulbs, I am a big fan of these:

D2S: Osram Xenarc 66240 Night Breaker Laser 4200K HID B21

Lasers are here from Osram in the form of their Xenarc 66240 NightBreaker 4200K XNL Laser Bulbs. Dominate the game like no other can. The Retrofit Source

www.theretrofitsource.com

Whatever bulbs you chose to go with, just be weary of knock-offs commonly found on Amazon, eBay, etc. TRS sells verified legitimate bulbs.

 

As stated above. Time for new bulbs.

 

Is it best that I replace both bulbs at the same time or since it is just the passenger side bulb that is failing, can I replace just the one?

 

I'd always recommend replacing in pairs. Usually the other is not far behind, especially if they are the same age.

The link I posted above is a pair of 2, just for that reason

What I usually do is keep the good bulb I took out as a spare, in case I need one in a pinch.

 

Going on 20 years, not too bad. Take your time and DO NOT jar it. Try not to touch the glass bits.
Second the recommendation of Osram. Hella is also a good brand (I think they were OEM) but avoid any brand you've never heard of.

 

Thank you to all who replied. I replaced the bulbs with Osram Laser Xenarcs as one user suggested and, needless to say, I am very impressed. I also took the time to polish the headlights so that I could best utilize the new lights. The headlights look amazing and the light performance is outstanding!!

 

Thank you to all who replied. I replaced the bulbs with Osram Laser Xenarcs as one user suggested and, needless to say, I am very impressed. I also took the time to polish the headlights so that I could best utilize the new lights. The headlights look amazing and the light performance is outstanding!!

Very happy it worked out for you! Nice job on the lenses too.