I installed new foglights about two weeks ago and the passenger side light seems a bit brighter. I thought it was the angle of the lights so I adjusted them with a tape measurer and made sure they were both straight but its still the same. Just yesterday I bought some aftermarket replacement bulbs and when I installed those one of them is still brighter than the other one. What could this problem be? Since it isnt the bulbs I was thinking it was maybe the reflector on the inside. Maybe one has better chroming or whatever. But other than that it could only be the wire right? Maybe one is getting more power than the other? Please help, thanks!

I would be looking for corrosion. Remove the bulbs on both sides and use a voltmeter to read the supplied power to each, then read the ground wire resistance on each side for comparison.

there could have been moisture inside the bulb and darkened the reflective surface of the bulb. Or the lens ould be to blame

Ok its not the bulbs if this is happening with two different sets of bulbs but thanks anyways. Im thinking its the power supplied so I'll get a voltmeter sometime later on and see what the problem is. At the moment its not biggie cuase it still looks nice. Car wouldnt start today though so I took it into Pep Boys and now Im getting a new starter so I have this to worry about.

How did you aim them with a tape measure?

Well its kind of hard to explain but on the back there is this thing that you twist and I kind of figured that if there was the same amount of spacing between the spring plate and the back of the light plate of both lights that they would be the same as far as the vertical angle goes. I may try to work on them some when I get my car back and it isnt raining because when I first installed them they were perfectly centered in the hole and the brighter ones seems a bit to the right but that shouldnt make a difference because I looked at both lights and many different angles.

You need to use a wall/garage door at night. and measure. I left my manuals in the car, but try adjusting them onto a wall, and look at them on the wall and after you adjust.

They're adjustable in the back, incase when mounted exactly the same onto the car, they don't line up.

Sounds good thanks! BTW this new starter rules! Starts up like a dream and sounds like a new car.

Here'* from the book:

Fog lamp verticle aim shall be performed with specification readings taken 7.6m (25ft) from fog lamp lense. Top of fog lamp beam to be 100mm +or- 50mm below fog lamp horizontal centerline. Vertical aim adjustment is done by turning verticle adjusting screw, found on rear of fog lamp assembly.


uhm...thats it, no pictures either...? It changes subjects after that but later there is a bit about headlight aiming. :?

I assume if one had a bad (e.g. oxidized) reflector, it would be kind of obvious in daylight when you compared one with the other. In fact I think one of mine is little shinier than the other in daylight, although they both light up pretty much equal at night.

I'd say you have either bad power or a bad ground to the offending light. Measure the voltage at each light and see what you get. Specifically, measure between the power and ground connection _at_ each light, and I think you'll find that one is worse than the other (in fact it pretty much _has_ to be, from what you're describing).

Now measure voltage on each between its power lead and a known-good ground, such as a wire clamped to clean metal under the hood. If the light is dim because its power lead is bad, you'll measure the same low voltage this way. If the light is dim because its ground lead is bad, you'll measure a higher voltage this way, because you've now provided a good ground path instead of a high-resistance one.