Replace a Prius headlight bulb

Notice: Update Below!

Like most people, I have a real life outside of computers. This evening after getting in from work I noticed the driver’s side headlight in the Prius was out. The tale of my journey follows.

Before he spent three decades as a cop, my dad worked as an auto mechanic. While I failed to take to the trade as well as my brother (OK, I didn’t take to it at all), I did learn a few things about fixing cars. One very important rule has always been: when in doubt go to the parts store and ask.

After surfing around a bit I found that some dealers charge up to $250 to replace a Prius headlight bulb.

Now if you have a Xenon HID headlight system (not everyone does) the bulb itself can cost up to $120. If you’ve instead got the standard Halogen bulb like I do, it will cost around $10 (Sylvania’s 9003/HB2, for example).

Let me note up front that most of the materials you’ll find on the Internet focus on HID bulb replacement. That’s probably because of the extreme expense involved for the part itself. But the mechanics of removing and replacing the bulb are almost identical whether it is a Xenon HID or Halogen.

The reason usually given by dealers for such a high cost of repair is that they have to pull the bumper in order to get at the bulb.

As Carolyn Coquillette, owner of the Luscious Garage in Oakland, CA, has said, “If their technicians are actually pulling the bumper, they’re idiots.”

Here’s a video Carolyn did to show why (don’t worry, it only takes 3 minutes):

Notice how the driver’s side bulb can be removed and re-installed without tools (the rubber gloves are to prevent fingerprints from getting on the new bulb — a very good idea!). Now to be perfectly honest, it probably helps to have small hands, nimble fingers and lots of experience removing and installing delicate parts. Pretty much the skills you’d expect of your average computer tech.

In the interests of full disclosure, doing the same thing on the passenger side requires a Phillips head screwdriver to remove some screws/clips from a cover to expose the back of the headlight assembly enough for you to get your hand down in there. So that would probably take a klutz like me a little longer (maybe 10 minutes).

Here’s another video by Brian Mathis that provides some more (very helpful) detail on technique:

Here’s Brian’s second video, showing how to install the your new bulb:

I just completed my own bulb replacement about a half hour ago as daylight was rapidly disappearing. Going into the project I had assumed that I had an HID bulb, in fact I had assumed that there was no other kind for the 2006 and later Prius. In preparation I had gone up to the Internet and purchased a pair of HID bulbs for $45, which I thought was a great deal. How much you want to bet the vendor won’t let me return them?

The most difficult part of the job turned out to be removing and then re-seating the headlamp weather cover off the back of the assembly. Although I have fairly small hands I probably should have removed the radiator cover to get some extra maneuvering room, I did not. I learned later than a common problem when removing the weather cover is that over time heating causes the bulb to adhere to the cover. The problem getting it back on was all “in my head”. I just didn’t have a good mental picture of how it worked. A flashlight and inspection mirror like I keep in my electronics toolbox would have been a big help, as would a diagram of the assembly that could have been printed off the Internet.

Once I got the bulb out I realized it did not match what I’d bought on line. Instead of one of these:

I was holding something that looked like this:

A quick trip to my local auto parts store and I was set straight by the guy behind the counter. Although I’d foolishly thrown good money away on a pair of HID bulbs, it was only going to cost me another $10 to finish the job because my car was equipped with the much less expensive Halogen lights.

When researching this project I had made the mistake of relying only on online sources — a quick trip to the auto parts store before I started would have resulted in my learning ahead of time that my lamps could be the Halogen type. One thing I read later is that most of the time it is only the cars with factory-installed foglights that have the HID bulbs. If you know what you’re looking for you might also be able to tell what kind of bulb you have by looking at it from outside (I think that might be a tough call for many people — not sure I could have made it).

In addition to the videos above, I later found a great article up on the site for Bentley Publishers:

Toyota Prius Headlight Bulb, Replacing

This “supplement” (the publisher’s description, not mine) to their full manual provides a lot of information (like the part about the bulb adhering to the weather cover) that makes it clear that whoever wrote it really knows what they’re talking about.