Need Electrical Wizard Help!
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Need Electrical Wizard Help! I have an 02 Camaro. A few years back, I did the mod to allow the high beams and low beams to be on together. I also did the mod that allows the fog lights to be on with the high beams. I used a write up that I found on this forum. Now I want to put it back how it originally was. As far as I can tell, I have returned everything to factory but the fog lights are not working properly. The fog lights will only turn on when the headlights are on. If the fog lights are on, the high beam indicator in the dash is faintly lit and the high beam bulbs are on but they are dim. The fog light switch will turn the fog lights and the high beams off and then the high and low beams function as they should. I am not finding anything that I have changed and forgotten about anywhere else. I'm hoping somebody could help me out. Just FYI, I am changing back because I got tired of the high beam indicator being on all the time. Thanks in advance for the help.
Joined: Nov 2003
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From: Jacksonville, FL (originally from Toronto Canada)
Your last sentence is the most telling... done correctly, the high beam and fog light mods will not cause the high beam indicator to stay on except when the high beams are actually in use. In other words, the mods have no effect on the high beam indicator light - it will work normally. If your modifications caused the indicator light to stay on when it shouldn't then one or both mods were done incorrectly. It would be most helpful to know exactly what was done. The symptoms appear to indicate a missing ground which is causing current to back feed through the headlamps. Note that it is normal that the fog lights are not available unless the headlights, or at least the parking lights, are on because they are powered by the parking light circuit.
Can you find the thread you followed when you did the mods? Perhaps you used the Firebird instructions (which are different from Camaro)?
Can you find the thread you followed when you did the mods? Perhaps you used the Firebird instructions (which are different from Camaro)?
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Your last sentence is the most telling... done correctly, the high beam and fog light mods will not cause the high beam indicator to stay on except when the high beams are actually in use. In other words, the mods have no effect on the high beam indicator light - it will work normally. If your modifications caused the indicator light to stay on when it shouldn't then one or both mods were done incorrectly. It would be most helpful to know exactly what was done. The symptoms appear to indicate a missing ground which is causing current to back feed through the headlamps. Note that it is normal that the fog lights are not available unless the headlights, or at least the parking lights, are on because they are powered by the parking light circuit.
Can you find the thread you followed when you did the mods? Perhaps you used the Firebird instructions (which are different from Camaro)?
Can you find the thread you followed when you did the mods? Perhaps you used the Firebird instructions (which are different from Camaro)?
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I have an 02 Camaro. A few years back, I did the mod to allow the high beams and low beams to be on together. I also did the mod that allows the fog lights to be on with the high beams. I used a write up that I found on this forum. Now I want to put it back how it originally was. As far as I can tell, I have returned everything to factory but the fog lights are not working properly. The fog lights will only turn on when the headlights are on. If the fog lights are on, the high beam indicator in the dash is faintly lit and the high beam bulbs are on but they are dim. The fog light switch will turn the fog lights and the high beams off and then the high and low beams function as they should. I am not finding anything that I have changed and forgotten about anywhere else. I'm hoping somebody could help me out. Just FYI, I am changing back because I got tired of the high beam indicator being on all the time. Thanks in advance for the help.
https://ls1tech.com/forums/appearanc...same-time.html
These is what I did and what I'm trying to undo
Joined: Nov 2003
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From: Jacksonville, FL (originally from Toronto Canada)
You followed those instructions exactly and yet your high beam indicator stayed on all the time? Sorry, that's not electrically possible unless there is a problem somewhere else in the circuit. Properly done, these two mods will make the low beams stay on when the high beams are used, allow the fog lights to remain on with the high beams (a pointless thing to do), and all switches and indicators will work properly (high beam switch, fog light switch, high beam indicator, and fog light indicator).
Check that the lighting grounds on each side of the upper radiator support are clean and solid - you could have a bad ground there which is causing current to back feed through the lights.
Check that the lighting grounds on each side of the upper radiator support are clean and solid - you could have a bad ground there which is causing current to back feed through the lights.
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Ok, so it looks like I've gotten it figured out. After checking the grounds as suggested, I found they were both still good. I took a few minutes to look over the wiring and be absolutely sure there was nothing else that I had changed. Then for some reason, something told me to unplug my LED high beam bulbs and see what happened. I swapped in a set of halogen bulbs that I had laying around and everything is working correctly now. So now I have new questions. Is this a common issue when using LED bulbs? What can be done about it? Is it just because I have low quality bulbs? Thanks again for all of the help.
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From: Jacksonville, FL (originally from Toronto Canada)
That's an interesting bit of information (that you have LED high beams) and it certainly explains the problem. You see, the circuit to turn off the fog lights with the high beams on is based on a very simple connection which runs the fog light relay coil ground through the high beam circuit. When the high beams are off, the relay coil can ground through the high beams but the halogen bulb filaments don't light up (at least not visibly) because their resistance is too high for the small amount of current involved. When the high beams are on, the relay has power on both sides (the fog light power plus the power from the high beams) blocking current flow and preventing the relay from tripping and turning on the fog lights.
Replacing the factory halogen lamps with LEDs means that very little current flow is involved and the back flow from the fog light relay is enough to dimly light the high beams.
You should find that putting the mods back in place but retaining the halogen high beams will now work properly. Or, you could leave the LED high beams and just do the fog light modification so that the relay has its own ground not dependent on the high beam circuit.
Replacing the factory halogen lamps with LEDs means that very little current flow is involved and the back flow from the fog light relay is enough to dimly light the high beams.
You should find that putting the mods back in place but retaining the halogen high beams will now work properly. Or, you could leave the LED high beams and just do the fog light modification so that the relay has its own ground not dependent on the high beam circuit.
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That all makes sense to me. I don't know why I didn't think to try that sooner. I guess I assumed that LED bulbs would include a resistor to take care of that problem. Is there anything out there that will work? I looked in the headlight upgrade sticky but most of it was about HID and projectors. I just want to swap out the bulbs.
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Verdad Gallardo Joined: Nov 2003
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From: Jacksonville, FL (originally from Toronto Canada)
LED headlight bulbs don't generally have resistors like turn signal bulbs because they don't have to worry about hyper-flashing. They do have current limiting resistors to prevent damaging the LEDs but those are not enough to limit current flow as low as produced by the coil of a relay.
You can fix the fog light problem by redoing the fog with high beam mod because it effectively disconnects the fog lights from the high beam circuit. And since you have undone the low beams with high beams mod, there would be no current back feeding to cause the high beam indicator to light. Other than that, perhaps the only way to put everything back to stock and still not have the problems you experienced would be to go back to halogen bulbs. That may not be much of a problem - unless you bought expensive LED headlight bulbs, they aren't producing any more usable output than the halogens did and how much do you really use your high beams anyway (unless you live in a dark rural area)? Frankly, LED headlight bulbs that you might get for under $100 from Amazon or eBay are junk and not worth the time it takes to install them.
You can fix the fog light problem by redoing the fog with high beam mod because it effectively disconnects the fog lights from the high beam circuit. And since you have undone the low beams with high beams mod, there would be no current back feeding to cause the high beam indicator to light. Other than that, perhaps the only way to put everything back to stock and still not have the problems you experienced would be to go back to halogen bulbs. That may not be much of a problem - unless you bought expensive LED headlight bulbs, they aren't producing any more usable output than the halogens did and how much do you really use your high beams anyway (unless you live in a dark rural area)? Frankly, LED headlight bulbs that you might get for under $100 from Amazon or eBay are junk and not worth the time it takes to install them.
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I ordered a set of resistors that plug in between the bulb and the harness. Hopefully that will take up enough current to make everything work properly. If not, I will just use the halogen bulbs. Thanks again.
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From: Jacksonville, FL (originally from Toronto Canada)
Adding resistors may solve the problem but doing so defeats the purpose of using LED bulbs - lowered current draw and less heat. The resistors increase the current draw and generate lots of heat. That's usually not a problem with resistors for turn signals because they're not on all the time (except maybe for some seniors in Florida) and they have a half duty cycle (flashing on and off). But headlights are on for much longer periods and the resistors will generate enough heat to melt plastic and possibly cause a fire.
You haven't said why you feel the need for LED headlights. With the possible exception of some very high end LED bulbs (vLEDs, Diode Dynamics, etc.), most LED bulbs are terrible when used in reflector housings such as those in Camaros and Firebirds - they produce an uncontrolled beam pattern that blinds other drivers and is ineffective for lighting the road.
You haven't said why you feel the need for LED headlights. With the possible exception of some very high end LED bulbs (vLEDs, Diode Dynamics, etc.), most LED bulbs are terrible when used in reflector housings such as those in Camaros and Firebirds - they produce an uncontrolled beam pattern that blinds other drivers and is ineffective for lighting the road.