Drivers side headlight dimmer than normal

The drivers headlight on my 06 all of a sudden went dim. I turn on the brights, the passenger side goes bright but the drivers stays dim and the fogs stay on and I haven't done the fig anytime mod. I checked the fuses for all the lights and they are fine. The lights are the

$34 Sylvania 9003 SilverStar Ultra High Performance Halogen Headlight Bulb, Brightest Downroad with Whiter Light (2 Bulbs)

Sylvania 9003/HB2/H4 SU SilverStar That I purchased a year ago next week.
What could this be? Any help would be greatly appreciated. Thanks in advance.

Edit: I have searched the interwebs a bit and have not had any luck.

 

Thread revival...

My driver side headlight is getting current, as the bulb glows, but is not nearly as bright as it should be. So much so, that I though it was completely out. When putting high beams on, there is no change. Stays the same.
The passenger side works fine.

Also, the high beam light on my dash is permanently glowing when the headlights are on (anything past dtrl on the stalk). Although it does get even brighter when I put my high beams on.

I have new Philips h4 bulbs in there, but the truck did just have the inner fenders modified, so components like the battery and fuse box were remounted and how the battery provides its ground to the truck (the short wire grounding the engine bay right next the the battery) was modified. It still grounds the chassis in the same area as oem, but that area is now tubes, not sheet metal.

Any suggestions?

I’m going to test tomorrow by swapping the bulbs and buying a volt meter to make sure the harness is putting out the correct voltage to the driver side.

Also going to send fabricator a text in case he has an idea.

 

I an wondering if this is a ground issue, but would just be speculating.

 

Report back after running these tests. If you swap bulbs side-to-side and it changes sides, it is obviously a bad bulb. If the problem remains on one side, it is a voltage issue and you can start tracing it from there. It seems unlikely to be a battery grounding issue as that would affect both sides.

 

True true, and it’d probably affect even more that the headlights too.

Fab guy responded that when removing headlights, the ground wire of the plug was a bit loose, so I’m pretty sure it’s that.

Will confirm tomorrow.

 

I'm betting it's the ground connection for the headlight. The low beam is feeding through the high beam and finding ground somewhere. Essentially the low beam and high beam are connected in series. That's why the light is dim and the high beam indicator is on.

 

This may help:

http://www.customtacos.com/tech.old...6toyewd/06toypdf/ewd/2006/tacoma/h/em01d7.pdf

 

Have you tried opening the hood and banging your fist down hard on the fuse box? That's what I do when this exact same thing happens to me. Just kidding, sorta, it does work for me.

I bought my '05 about 4 years ago with a little over 100,000 miles on it. A few months later it started doing the same thing as described above, drivers side headlight about 1/4 as bright as it should be on both bright and dim and bright indicator in dash glowing faintly regardless of switch position. I've spent hours trying to find the problem and while I haven't yet discovered a permanent fix I redneck engineered something to keep it from happening.

In the fuse box, next to the fuses are three connectors. I discovered that wiggling the largest one would cause the light to come back on to full brightness, which is odd because that connector doesn't have anything to do with the lights. (You can unplug it completely and they stay on.) My "fix"? I wedged a wire nut down beside the connector to keep pressure on it and, voila, no more dim headlight.

Obviously there is something slightly loose somewhere in the fuse box, and I have gone as far as taking it apart far enough to flip it over, but when I saw the eleventy- billion wires coming out of the bottom I got a little scared of screwing something up and just left it alone. For the time being my "fix" works.

Edit: Thanks to @Jimmyh for the wiring diagram. I printed it off; come spring and warmer weather maybe I'll tackle this again.

 

Here's a picture of my fix described in the above post. You can see the orange wire nut wedged up against the connector. That was all I needed to do to keep the light working. Beats the hell out of opening the hood and thumping the fuse box every morning. YMMV

 

Looks like my problem was that the ground wire was very loose, almost pulled out, of the back of the h4 socket/plug. Barely making contact.
Soldering it back into place should take care of the issue.
Going to do that his afternoon.

 

You were correct sir