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fog lights constantly burning out!!!


dmorlow
02-28-2004, 12:48 AM
I have a terrible time keeping my fog lights working. I have heard rumors that the Auroras hold water in the fog light area which causes the lights to burn out. Is this true? I cannot seem to keep the fog lights working for more than a month or so and one burns out. My headlights have never burned out. It would seem that they would burn out about the same intervals. Does anyone know why the fog lights burn out so much? Is there a way to prevent it? If it is a water issue, I was thinking of drilling a hole in the bottom of the fog light spot to drain any water in that area. But if everyone here comes to the conclusion that doing this is a stupid idea and that would never be the cause of the problem, then this will save me from drilliing unnecessary holes in my car.

Thanks for any input!!!

David

Indy8
02-29-2004, 02:52 AM
Drilling the holes is supposed to work. Smallest bit you can find! Are you taking care to not touch the bulbs with bare fingers when installing? Skin oil causes hot spots that make them burn out in no time.

dmorlow
02-29-2004, 05:50 AM
I've known about the oil from the hands and have always made sure to not touch the bulbs. So drilling the holes should work?

Indy8
03-02-2004, 12:17 PM
If it's being caused by moisture, yes.

apostolakisl
03-13-2004, 12:12 PM
This is apparently a common problem as there is a technical service bulletin on the issue. I don't have the actual tsb but I came accross the summary.
Technical Service Bulletins Summary

Make: OLDSMOBILE
Model: AURORA
Year: 2001
Service Bulletin Number: 030842008
NHTSA Item Number: 10004383
Summary Description:
FRONT FOG LAMP BULB LIFE IS TOO SHORT. *TT

dmorlow
03-13-2004, 09:07 PM
I don't see that bulletin board. I have searched for the bulletin board number using google and dogpile. I have visited numerous GM repair sites that have service bulletin sections to the site. I also signed up for a subscription to www.alldata.com and they don't have anything on the fog lamps burning out. Is there anyway you could tell me which site you found this on?

apostolakisl
03-13-2004, 09:54 PM
http://www-odi.nhtsa.dot.gov/cars/problems/tsb/tsbsearch.cfm

ugsrich
03-18-2004, 08:53 PM
I want to make sure I understand. The fog-lamp burn out problem being discussed is for the orginal Aurora body-style 95-99 (I am original owner of a '95)? I see someone quoting a tsb for 2001. I have had similar burn-out problem (great care taken to avoid skin contact with bulb). I presume that the very small hole is drilled in the bottom of the refector housing? Please elaborate if you have performed this operation and suggest a specific location at which to drill the small hole. Thanks for your help.

Indy8
03-18-2004, 11:00 PM
The bottom, center of the lens or, the lowest possible drain point for condensation.

ugsrich
03-20-2004, 08:27 PM
Ok. So. I dropped all the air dams and removed the fog lamp housings from my ’95 today. When I got them out I noticed what appears to be some sort of breather hole in the housing (or something like that) on the bottom just below where the lamp itself would be positioned. Are you familiar with this? I chose not to drill any holes at this point pending a little more feedback/input.

Any additional thoughts?

dsatt12
03-20-2004, 09:26 PM
Nothing terribly specific to the car, but light bulbs of all kinds burn out incredibly fast if they are run on too low of voltage. Can you get a multimeter on the lead and see what is being supplied? If there is a problem I doubt you could track it down on your own, but it'd let you know you needed to talk to an electrical shop to fix it.

ugsrich
03-21-2004, 09:20 AM
Only my fog lamps burn out at what I consider a grossly accelerated pace. The hi/lo beam and turn signal lamps are all OE (i.e. never been replaced). The only other exterior bulb that failed was one of the rear license plate lights. I don't believe it's related to voltage/current in my particular case.

dmorlow
03-22-2004, 02:35 PM
actually i am not 100% convinced that drilling the holes is going to help anything. and i would rather not drill the holes until i am 100%. i don't believe it is happening because it is holding water. i think it is more condensation that is building up on the light bulb. and the condensation isn't going to go down unless it is air tight inside the glass. and i don't believe it is. i think that is probably the problem. i am actually leaning more towards just replacing the factory fog lights with aftermarket sealed fog lights. The next time I have my car on the hoist, I am going to look at how big of an opening there is behind the glass and how hard it would be to remove all of the factory stuff so I can place after market lights behind the factory fog light glass.
But if there is a way to fix the factory system, I would rather. But I don't want to start drilling holes on a hunch.

cmdrgala
03-23-2004, 11:04 AM
Hello:

I had the same problem,of the fog lights burning out too soon.
My issue was with road vibration to the plug, make sure you push and turn the plug tight.

Never have water issues, but you might want to drill a small hole toallow the water to darin out. Or pull the hole assembly out and water seal along the edges. Or just buy another one on Ebay, are about $ 20.00.

Good luck.

ugsrich
03-23-2004, 05:43 PM
I would like to buy a new housing/reflector/lens assembly for the fog lamp of my '95. Oxidation has completely taken its toll on the chromed reflecting surface on the primary parabolic reflector. In other words the chrome has been completely etched away as a result of the moisture and so there is no reflected/focused illumination from the fog lamp unit.

I checked eBay and found no "hits" for fog lamp housing/reflector/lens/mounting assembly. A check of GM-Parts-Dealer.com indicates that one of these complete assemblies is about $130. I'm not interested in paying quite that much. Any other sources for these parts?

cmdrgala
03-23-2004, 06:04 PM
Just be patient and check daily, check both under
(Olds Aurora and Oldsmobile Aurora)

dmorlow
04-05-2004, 08:44 PM
Well, I came across a bulletin that explains this issue. It says the reason why the lights blow out too much is because there is too much voltage going to the lights. And there is a kit to fix it. I guess it is just a resistor. And you need to get one for both sides.

dred98
04-05-2004, 09:53 PM
Did the bulletin say it was a problem in specific years or did they fix it somewhere along the line?

dmorlow
04-06-2004, 01:03 PM
Ok, here's the bulletin...

Models: 2001-2003 Oldsmobile Aurora

Condition
Some customers may comment that the front fog lamp bulb life is too short.

Correction
To correct this condition, install a fog lamp jumper harness that will slightly reduce the voltage to the front fog lamps. This will NOT cause a noticeable change in the brightness of the fog lamps. Use the following procedure to install the front fog lamp jumper harness:

1. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle in the General Information sub-section of the Service Information (SI Document ID #439413)

2. Remove the front air deflector. Refer to the Air Deflector Replacement- Front procedure in SI (Document ID #632192)

3. Disconnect the electrical conneectors from the back of both fog lamp wiring harnesses.

4. Cut off the fog lamp connectors from both the front fog lamp wiring harnesses.

5. Using the contents of the jumper harness kit, P/N 25754206, splice in the new fog lamp wiring harness and connector. Use another jumper harness kit for the front fog lamp on the opposite side of the vehicle.

6. Connect both front fog lamp electrical connectors.

Part number
25754206

Description
Jumper Harness Kit

Two Kits Required Per Vehicle

Parts are currently available from GMSPO.


So now everyone knows what I know. But it does say this is for 2001-2003 and I have a 1995. But it sounds like the same issue so it is probably the same problem I am having.

dmorlow
04-06-2004, 01:19 PM
Here's the pricing information from www.gmpartsdirect.com

GM PART # 25754206
CATEGORY: All
PACK QTY: 1 CORE CHARGE: $0.00
GM LIST: $61.10
OUR PRICE: $34.83
DESCRIPTION: HARNESS

Does anyone have any idea what they are changing in this new harness? Is it just resistance? $60 sounds like a lot of money to spend on my fog lights. Especially if I can just solder in a resistor into the positive line and accomplish the same thing.

dmorlow
04-26-2004, 09:00 PM
So does anyone know how I could lower the voltage on that line? I was thinking I could just solder a resistor, but then I figured out today that it would only produce the exact opposite results that I wanted. According to the V=I*R, if resistance increases, so will voltage. So I would have to find a way to decrease resistance which sounds impossible, or I would have to decrease current. How would I go about decreasing current without affecting resistance?

dsatt12
04-27-2004, 05:42 AM
According to the V=I*R, if resistance increases, so will voltage. So I would have to find a way to decrease resistance

So you replace all your wires with some big fat 00 guage... Seriously, it's pretty easy to reduce the equivalent resistance, and therefore current. Since you bring up Ohm's law, you can manipulate that using Kirchoff's rules. To get right to the thick of what that means here is that for resistors in parallel voltage is constant. The equivalent resistance in a simple parallel arrangement is 1/Req=1/R1 + 1/R2 +... and so forth. So if you measure the resistance of one of your fog lights, say 20 ohms. Now you add a jumper wire with another 20 ohm resistor across the positive and negative leads to the bulb, and you get 1/Req=1/20 +1/20. Your new resistance (Req)=10 Ohms and your new current going through the fog light should be halved. The question then is how much current do you need to reduce things by? Ask if you can pretty please see one of their harnesses multimeter in hand :) Perhaps you could buy one from the dealer and then return it. If indeed this is how they are going about this fix, if you can get your probes down into the harness it should read a resistance across the positive and negative leads instead of an open circuit.

P.S. If you want to look at the circuit another way, my physics teacher used the water pipe analogy. You've got a pipe with water going through it. If you make another loop on the pipe, some of the water (current) is going to flow through it instead. If the pipe is really big around (resistance), a lot of the water goes there instead. If the pipe is the same size, half the current goes there instead.

dmorlow
04-27-2004, 05:52 AM
I bet you are right. The bulletin does say that you replace the original harness with a jumper harness. And what you are saying does make sense. I'll have to get my car up on the hoist and check what the resistance is and then I'll buy a resistor that I can add in parallel to the light. Does anyone know where you can get a resistor that will be tough enough to put next to the light that can stand the weather climate? I guess I could just buy a normal resistor and solder it in and then just put electrical tape around it. But if they have a resistor that has a housing to it for rugged climates (made to be put to a practical use like this).

dmorlow
04-27-2004, 05:57 AM
But when doing this, would I need to measure resistance of the actual socket or would I just measure resistance of the bulb? Because if I have to measure the socket's resistance, I would have to actually cut the socket off the car or I would end up taking the resistance of the rest of the wire into consideration. I don't know if I am brave enough to go into the dealer and ask them for a socket and then pull out my meter and measure resistance and tell them, "thanks" and walk out.

dsatt12
04-27-2004, 06:07 AM
How I'd approach it depends on which end of the connector you can get to. If you have the male pins, and the harness you unhook from the bulb or the leads is female, then just measure the resistance of the bulb and whatever wiring is in there. I think the wiring is going to have a pretty negligible resistance compared to that teeny ass little filament going through the bulb though, so just the bulb would likely do just as well.

I would think a regular resistor shouldn't have too much trouble with heat and or vibration as long as it's soldered in place. The leads would probably rust if not protected from moisture, but some tape should do fairly well.

Just a half assed guess, but I'd try a resistor 4x as big as the bulb. You'd knock off 20% of the current that way.

dmorlow
04-27-2004, 09:58 AM
Well your half assed guess is better than any guess I can come up with. Thank You!!!

dmorlow
04-27-2004, 10:33 AM
Ok, I have another question though. I am not 100% sure this is going to work yet. Can you answer this question.
V=I*R
In this equation, doing what we said above, if I decrease resistance, it will lower voltage going to the light supposedly. But I am starting to think, lowering resistance will lower the voltage or it is going to increase current. Both senerios will make the equation satisfied. If it ends up increasing current, then voltage stays the same and I have accomplished nothing. So it really comes down to what is the variable and what is the constant? It would seem to me that voltage is coming from the battery and it is a constant 12v. So decreasing the resistance is only going to increase the current and voltage won't change at all. Or do you think otherwise. Remember, I know just enough about electricity to be dangerous. I really have no formal training in electroincs. So this reasoning has no logic to it other than what my brain came up with and the very limited electronic knowledge I picked up from talking to people.

dsatt12
04-30-2004, 11:00 PM
It will work, provided that high current really is your problem. Your reasoning makes sense as far as you took it. The trouble is I skipped over a few of the intervening steps to provide the answer before. If you wire up this resistor in parallel so the juice can go either through the bulb or the new resistor you hooked in, you're really making two different circuits for the purposes of applying ohm's law (V=IR). For figuring that stuff out, you're really supposed to make an equation for every possible path the electricity can take, then solve the whole system of equations. Then there's the whole question of figuring out which way the current is flowing though what loop. Kirchoff's rules are just special case simplifications to doing it that way. Anyway- it'll work. Stop making me relive EE 440!


A good rule of thumb to remember is that voltage is constant in parallel, and current is constant in series. That water pipe analogy really does help the brain wrap around this stuff too. Water pressure is voltage, the actual water flow is current, and pipe size is resistance (big pipe=little resistance and vice versa).

dmorlow
05-02-2004, 05:07 PM
Ok, so today I took out my multimeter to my car and started to take some measurements so I could maybe get an educated guess on what size resistor to put in parallel with the light. When I measured voltage, I got 11.98. For current, I got 2.65. But I am not sure what units that is. I had the meter on the 20m setting. And I measured the resistance of the bulb and I got 0 ohms (which makes sense I guess). I really didn't feel like cutting off the whole socket to measue resistance of the whole socket even though I did have to cut one wire to measure the current. But in this situation, it doesn't quite work with the equation. How does 11.98 volts equal 2.65 amps (or whatever units the 2.65 is in)? Actually in this situation, resistance is 0, so it would be 11.98=2.65*0 which says 11.98=0 which makes no sense.
Today we had a family reunion and I talked to one of my cousins. He is an electrical engineer and I asked him really quick what he thought I should put in parallel with the light without getting into too much detail and he just whipped out a number of 5k ohm resistor. Does this make sense. For all I know, he didn't feel like talking about electronics and just whipped out a number to get me off his back. I am not sure if I should put in 5 for r in the equation or 5000 for r. If I put in 5 and make the current the unknown variable, current would solve for 2.396 which lowers current which might help and maybe he is right. But if I put in 5000 for r (seeing it is 5000 ohms), then current is .002396 amps which seems awefully small.

Remember, I know nothing about electronics other than what I pick up from talking to people. Does anything I am saying here make sense? Does a 5k ohm resistor make sense to put in parallel with the light with the numbers I measured today?

Thanks for any help!!!

dmorlow
05-02-2004, 05:10 PM
And I should clarify for above that the meter was in the 20 m setting when I took the current measurement and not the 20 mu setting (the letter that looks like an m and a u in one letter).

dsatt12
05-02-2004, 08:27 PM
Ok, so today I took out my multimeter to my car and started to take some measurements so I could maybe get an educated guess on what size resistor to put in parallel with the light. When I measured voltage, I got 11.98. For current, I got 2.65. But I am not sure what units that is. I had the meter on the 20m setting. And I measured the resistance of the bulb and I got 0 ohms (which makes sense I guess). I really didn't feel like cutting off the whole socket to measue resistance of the whole socket even though I did have to cut one wire to measure the current. But in this situation, it doesn't quite work with the equation. How does 11.98 volts equal 2.65 amps (or whatever units the 2.65 is in)? Actually in this situation, resistance is 0, so it would be 11.98=2.65*0 which says 11.98=0 which makes no sense.
Today we had a family reunion and I talked to one of my cousins. He is an electrical engineer and I asked him really quick what he thought I should put in parallel with the light without getting into too much detail and he just whipped out a number of 5k ohm resistor. Does this make sense. For all I know, he didn't feel like talking about electronics and just whipped out a number to get me off his back. I am not sure if I should put in 5 for r in the equation or 5000 for r. If I put in 5 and make the current the unknown variable, current would solve for 2.396 which lowers current which might help and maybe he is right. But if I put in 5000 for r (seeing it is 5000 ohms), then current is .002396 amps which seems awefully small.

Remember, I know nothing about electronics other than what I pick up from talking to people. Does anything I am saying here make sense? Does a 5k ohm resistor make sense to put in parallel with the light with the numbers I measured today?

Thanks for any help!!!

Allright- I went back through all of these posts, and I realized there is a teensy problem. The post that detailed the TSB said it was excessive VOLTAGE that that at fault, not high current, as I wanted to fix...

As to what you measured, the current would likely be in amps. Your resistance might be a wrong setting on the meter, I dunno. It should have a measurable resistance.

Now, since these are supposedly 40w max bulbs, your current jives pretty well. The max current for 12v would be around 3.3A. Coincidentally, solving that figure gives about 3.5-4.5 for resistance in Ohms, depending on if you plug in 3.3A or 2.65A. Sorry I didn't thin about using the power rating of the bulb earlier to give you some ballpark figures.

The main difference were talking about to change is just to put the resistor in line in one of the wires instead of across the leads. In this case a tiny resistor (.5 Ohm?) would knock off a volt or two. The trouble with that reasoning is why the heck would almost exactly 12v burn out your darn fog lights too early?

Now, I've totally been having to dust the cobwebs off this stuff in my head, so I found this page that helps with some of these concepts if you're interested: http://www.tpub.com/neets/book1/chapter3/1-30.htm
While I *am* an engineer- that page likely sums up about 75% of the lead I have on knowing about this stuff. The closest I come to using this is keeping track of what color wire went tp what terminal when I change the oil in a gearbox at work.

At this point, my best suggestion would be since you said your had to cut a wire to get a current reading (or did you just strip it a bit?), add a resistor in line with the bulb. Either side of the harness will do. You might notice it being dimmer than the other if you only do one side. This would be easy to try and easy to fix if there isn't any improvement. For a short time, you could probably even rig something up with a short piece of wire with your resistor and use wire nuts to hook it up so see if there is improvement (or even just the resistor if it has long enough leads). Just tape everything up and go with it for a few weeks.

I'm sorry I didn't notice earlier that we were working on the wrong thing. I guess that's what I get for working nights...

dmorlow
05-02-2004, 08:47 PM
Well, as much as I know, you have to cut the wire to read current. So that is what I did. I thought you have to cut the wire and make the meter part of the circuit to measure the current in the circuit. But you say to put in a .5 ohm resistor and my cousin says to put in a 5k ohm resistor. I guess I need to see it in the equation to prove to me that it works. And I am not that great at using that equation. I am pretty sure my math in the previous post isn't correct. Do you see what I am doing wrong?

GSRtrackside
06-26-2005, 03:53 PM
DUDE you must have a ''fuse'' from the positive battery to your ''hot wire'' for the fog lamps. i use to have a burnout problem but i found that you need a correct fuse to help the suge. that was my problem, and usually condensation isnt a big problem unless its not a name brand. so add a fuse if not that, its your wiring,

dmorlow
06-26-2005, 04:55 PM
Well, I don't know what happened with that car. I cut the positive wire on one of the sides of the car to measure the amps going to the light. I asked someone what the amps were supposed to be. They weren't over. So I taped them back together and after that day, I went about a year without one blowing again. But I sold that car about a half a year ago now. It was more problems than it was worth. In the last few months, I spent around $3,000 in repairs on it. Overall, I spent over $6,000 on a car I paid only $5,000 for. I just sold it and bought a brand new Chevy Impala with a 100,000 mile warranty.

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