Headlight Adjustment

Replaced a headlight bulb. Easy as I had the windshield washer tank removed. With those 3 prongs that force you to put the new bulb in just like the old one was, I figured there would be no adjustment needed. Wrong! I did a search on the forum and came up with a diagram that only showed one of the adjustments, but of course when I looked at them just now, I see nothing that looks like the diagram. So, a question on how to adjust the lights. This is on the passenger side.

Tight space to get a camera in, so took a mess of photos just to get these two.

First photo shows some plastic thing where the red arrow points to near the top of the headlight fixture. Is this something that just comes off to expose the adjustment, and would this be for vertical or horizontal adjustment?

What is that connector with the blue arrow?



On the second photo the red arrow points to kind of what I expected to see as an adjustment for the headlights on the bottom of the light fixture. Would this be for vertical or horizontal adjustment?

 

The 2.0 Gen headlights have 3 connections. h4 for low and high beam. Sidemarker for parking lights near the lateral edge. And DRL / turn via 3 wire connector towards the midline of the vehicle.

vertical adjustment I remember as being a round Philips head screwdriver from above, same as third Gen. But it was late and dark so I may be mis remembering. It meshes with the gear teeth. Round barrel works better than hex so it glides.

Most likely you do not need to mess with horizontal adjustment. Make sure your bulb is properly seated before beginning.

More precise instructions on aiming are here:

https://www.danielsternlighting.com/tech/aim/aim.html

The hardest part is finding a location.

 

You come in from the top, through the two little walls on the back of the housing.
The blades of your Phillips screw driver will act like the pinion gear, and the adjuster star is the ring gear.

 

Before you adjust anything, I have a few questions. First, what kind of bulb did you install? Generally speaking, if you installed a halogen H4, you shouldn't have to adjust much if anything. Drop in LED or HID bulbs are a whole different story.

Second, make sure the bulb is fully seated in the housing opening. It's actually quite easy to install the bulb incorrectly and / or not fully seated. This is what it should look like before the dust shield goes on:

 

I threw the package away, but it was a Nappa part 9003. It’s installed correctly. Without the windshield washer reservoir taking up all the room, it was real easy to do.

https://www.napaonline.com/en/p/LMPBP9003N

I keep hearing that a phillips head screwdriver is needed to adjust the lights, but a video I found and what I see in the second photo shows a 10mm socket. In my first photo, if that black plastic thing is just a cover for the adjustment, then why doesn’t the lower one in my second photo have a black plastic cover? Every time I have ever had to remove a plastic part on this truck, I have broken them, hence, I’m hesitant to remove that black plastic cover.

 

Adjustment can be found here.
https://www.tacomaworld.com/threads/the-ultimate-headlight-upgrade-h4-not-led-or-hid.398066/

 

Finally got a break in the rain to adjust the headlight. The diagram I found in that thread showed a screwdriver to adjust headlights and another thread, or video on YouTube (I forget) showed to use a 10mm socket. Well, it took a 5/16 socket. None of my metric sockets worked and a screwdriver would have been too slow.

The diagram also showed to turn it counterclockwise for down. It was clockwise to turn it down. I even removed the light bulb to make sure it was seated correctly. It was.

The headlight that I did not replace had a horizontal line at the top and the new bulb did not. I never thought to take a camera with me, or I would have taken a photo. I did get the light to not point up into the air, but if I stood in front and looked at the headlight, the new one was still too bright on low, but I must have turned it more than 20 times to get it down to where it is now. I may have to take it to a shop to have them aligned correctly. This turned out to be quite the ordeal for me at the age of 76 and someone who does not like to work on vehicles, other than changing my oil and greasing joints and some other easy stuff like changing filters.

 

Turning the screwdriver counterclockwise (from above) actually turns the head of the adjustment bolt (from the side) clockwise. Hard to explain, but since the screwdriver is on the back side of the adjustment bolt, it ends up turning it the opposite direction. The instructions are correct for screwdriver adjustment.

As for the rest... You may be way past the normal operating range effectively making your light beam flipped? I have never turned that adjustment screwdriver more than a maybe 4 or 5 turns? And it takes a screwdriver a couple turns to turn the whole bolt once. If you turned the whole bolt 20 times . . .

 

That makes sense if you are looking down from the front. However, the diagram shows it from the back, and that is how I got clockwise to turn it down. I was looking at it from the same direction as the diagram showed if that makes sense.

“You may be way past the normal operating range” I have no clue as to what you mean by that.

 

Recently replaced my headlight assemblies and for the life of me was unable to adjust down the passenger beam. Finally brought it to a shop and was told the bulb had been installed UPSIDE DOWN...after correcting that, he was able to dialed it in . How the heck that happened is a mystery to me...I have a gift I guess...LOL

 

If your headlamps were adjusted correctly originally, it's almost impossible for a new H4 bulb to need re-aiming (if it's installed correctly).

Have you double-checked that the bulb is really seated in the headlamp reflector? On my Gen 2 it seems like every time I change a bulb the wire spring keeper falls out and I have to fiddle with it to get it back in the correct position to hold the bulb in the right place. In the dozens of headlamps I've had and changed H4 bulbs, I've never seen one with the wire spring so easy to dislodge.

 

Here's a tip that may help you - and others - with the problem of the clip falling out. I applied a dab of RTV at the pivot point (left side of the above picture) after the bulb and clip were properly in place. This prevents the clip from falling out, but still allows it to pivot.

 

Clever idea. A dab of hot melt glue might work too to hold the clip.

 

I believe so. I remember on mine part of the adjusters had this PITA cap on them for no reason that I understand
making it even harder to access, in the already tight clearance to stick a wrench on the tiny hardware
So I took them off to throw out, no problems

aiming; find a wall and eyeball it. You'll see on the road at night; if it's not perfect, do it more until it is. Not a lot at a time.

I appreciate that, coming from cars where bulbs are changed by removing a wheel

 

Here is what the headlight looks like now. If anyone can see anything wrong with how it is installed, let me know. By the way, that wire spring keeper is so dang stiff, my thumb got so sore that I had to use a pair of pliers to undo it.

 

That bulb is clearly not sitting properly. It needs to rotate clockwise til the bulb tabs sit inthe recesses of the housing. At which point it will also “drop” further into the housing. The top tab of bulb is at the 11 o’clock position and needs to be at the 12 o’clock. Can also see the void/space around the top of bulb . I’m sure the spring will be easier on the fingers afterwards. Look at pic in post #12

 

As noted above, the bulb is installed incorrectly. The tabs have to go in the recesses. See the red marks in the following photo

 

Thank you for taking the time to use my photo to show me my error. I may or may not have figured it out on my own. Once the headlight was seated correctly, I no longer needed a pair of pliers to open the spring. Headlights are now properly adjusted.

 

good info .