Fog Lamp Conversion To Driving Lights
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wait....so you changed the fogs to driving lights? So they have low and high beams now?
huh? I am not getting this...what did he do? :scratch:
huh? I am not getting this...what did he do? :scratch:
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My post is very detailed, but what I did is very simple.
I put a 7" European low/high beam lamp in place of the stock fogs.
When I use the fogs I have the 80w low beams on, when I put on the highs I have the 100w bulbs on.
I put a 7" European low/high beam lamp in place of the stock fogs.
When I use the fogs I have the 80w low beams on, when I put on the highs I have the 100w bulbs on.
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That's correct.
I can run just the fogs.
Fogs & lows.
Highs & highers.
My avatar shows the highs on before they were beamed. You can see how much whiter the upgrade is.
I can run just the fogs.
Fogs & lows.
Highs & highers.
My avatar shows the highs on before they were beamed. You can see how much whiter the upgrade is.
#25
Originally posted by PONY XPRESS@December 11, 2004, 4:47 PM
As promised find enclosed info for the fog lamp to driving lamp conversion. This is lengthy. Pics next post.
I have always considered lights like HP, you can't have too much. Most 2 headlamp systems are not adequate for the speeds of the vehicle. The new Mustang can out drive the stock high beams by the end of 3rd gear. The fogs are a joke & are only good for day time running lights.
I have a supplier that can supply you with the package if you have interest. The enclosed pics were taken before I beamed the new lamps which are too low, but you can get the idea of the way they will perform. I will go out this weekend one night & beam them & report back. With my past experience with lighting I look forward to great results. At least twice to three times the increase in light, as these lights are whiter & brighter then OE. There will also be upgrades for the stock bulbs shortly which will make this a world class system.
I used 7" H-4 round lamps & buckets from a VW Golf II. 80-100watt H-4 Super white bulbs (look blue when not on) a Hella fused relay & Hella headlamp connectors. The H-4 is a low & high beam lamp.
When I first took the grill apart to inspect & measure, I removed the horns & replaced them with Hella 2 tone air horns. First, the stock horns are not adequate & they may be in the way of the conversion. (You may have to relocate them, bend the bracket, or go with the air horns). Second, air horns are so much better especially at highway speeds. The new stereo systems & exhaust make older horns obsolete. People can't hear you. Mounted the air horns in the lower valance left side. Trick with the horns are to keep them low, facing the ground, & use as little air line as possible. Sounds great.
To remove the grill open the hood. You will see a cover over the radiator support with 6 clips. Pull the pins up & remove the clips & cover. Then with a long big head flat screw driver pry the soft rubber tabs around the stiff tabs of the grill. Do the 2 by each headlamp first, then the four on the bottom. Put a cloth on the bumper cover so as not to scratch & pull out grill. Unplug the fog lamps by pushing on clip & pulling. Grill is out. Remove stock lamps & custom fit the new.
The buckets & grill have to be trimmed, drilled & ground to fit. I won't go into details, but the old adage about measure twice cut once applies hear. One of the pics shows the stock lamp & an upgrade from behind. You will use the stock torx bolts (size 25) in the stock holes.
A couple of tips. Be careful not to block the tabs on the bottom of the grill, you must trim enough to give them room to clip. You have 2 adjuster screws, 1 for vertical 1 for horizontal. Since the stock lamp is 6.75" & the new is 7.0" the adjusters are out of the stock bucket area, so you have to make holes in the flat part of the grill for the adjusters. A little tricky, but you can't see them unless your looking for them. Paint the buckets flat black as they are bronze new. A small portion of the bucket can be seen through the grill.
OK, wiring. The plug for the back of the lamps is the standard 3 wire plug. Looking at the back of the lamp you have 3 tabs on the bulb.
12 O'clock is the low beam. Yellow
3 O'clock is the ground. White
9 O'clock is the high beam. Brown
The left side fog plug:
Blue with black stripe is "+"
Black is "-"
The right side fog plug:
White with red stripe is "+"
Black is ground.
Cut the male end connector off of each Hella wiring lamp harness so you have 3-4" of wire on each female connector
Each new H-4 lamp has 2 connections that go to the stock fog harness. You will connect the low beam to the "+" side & you will connect the ground.
The stock relay for the fogs should be adequate for the 80w low beams. The circuit also has a 15 amp fuse so the fuse will blow before any damage can happen to the harness. If I find the relay is insufficient I will then wire a separate unit, but I do not for see it.
Now for the high beams. The Hella relay has 4 connections:
# 85 is ground
# 30 is 12 volts "+" in.
# 87 is out to the lamps.
# 86 is the 12 volt "+" trigger.
I ground (85) the relay to where I mount it. This way it is a short wire. I used one of the studs that hold the horn bracket to the radiator support for the mounting. Use the one behind the support.
I got my 12 volt "+" (30) from the fuse & relay box by the right side headlamp. Pull the cover & you will see a bolt in the back that holds a cable supplying power to the system. Unbolt the bolt & attach a wire eye connector.
To trigger the relay (86) I picked up the high beam circuit off of the right side headlamp. The white wire is the hot side for the high beam. This way whenever you put on your high beams or flash other vehicles all four lamps come on at the same time. No need for extra switches in the car.
The (87) connector then goes from the relay to the brown wire of each Hella lamp harness.
I put all of the wires into a 3/8" black wire loom, tape & wire tie everything up & it looks like it is factory.
It is not hard, just time consuming. You will find this the be the best $100 you can spend on your car.
Find your favorite wall or road & beam them as you like. I hope this will help some of you guys & gals out. Enjoy
I have gotten a few requests already so here is the supplier of the lights & air horns. I have no affiliation with them.
Classic Garage
997 Route 6
Brewster, NY 10509
845-940-1900 Mon-Fri
Ask for Stewart or Tim & tell them that the Pony Express referred you about the 05' Mustang Fog Conversion.
You want the 2 lamps & buckets, comes assembled. Golf II
2 80-100watt H-4 Super White bulbs
1 Hella fused relay
2 Hella lamp wire connectors
As promised find enclosed info for the fog lamp to driving lamp conversion. This is lengthy. Pics next post.
I have always considered lights like HP, you can't have too much. Most 2 headlamp systems are not adequate for the speeds of the vehicle. The new Mustang can out drive the stock high beams by the end of 3rd gear. The fogs are a joke & are only good for day time running lights.
I have a supplier that can supply you with the package if you have interest. The enclosed pics were taken before I beamed the new lamps which are too low, but you can get the idea of the way they will perform. I will go out this weekend one night & beam them & report back. With my past experience with lighting I look forward to great results. At least twice to three times the increase in light, as these lights are whiter & brighter then OE. There will also be upgrades for the stock bulbs shortly which will make this a world class system.
I used 7" H-4 round lamps & buckets from a VW Golf II. 80-100watt H-4 Super white bulbs (look blue when not on) a Hella fused relay & Hella headlamp connectors. The H-4 is a low & high beam lamp.
When I first took the grill apart to inspect & measure, I removed the horns & replaced them with Hella 2 tone air horns. First, the stock horns are not adequate & they may be in the way of the conversion. (You may have to relocate them, bend the bracket, or go with the air horns). Second, air horns are so much better especially at highway speeds. The new stereo systems & exhaust make older horns obsolete. People can't hear you. Mounted the air horns in the lower valance left side. Trick with the horns are to keep them low, facing the ground, & use as little air line as possible. Sounds great.
To remove the grill open the hood. You will see a cover over the radiator support with 6 clips. Pull the pins up & remove the clips & cover. Then with a long big head flat screw driver pry the soft rubber tabs around the stiff tabs of the grill. Do the 2 by each headlamp first, then the four on the bottom. Put a cloth on the bumper cover so as not to scratch & pull out grill. Unplug the fog lamps by pushing on clip & pulling. Grill is out. Remove stock lamps & custom fit the new.
The buckets & grill have to be trimmed, drilled & ground to fit. I won't go into details, but the old adage about measure twice cut once applies hear. One of the pics shows the stock lamp & an upgrade from behind. You will use the stock torx bolts (size 25) in the stock holes.
A couple of tips. Be careful not to block the tabs on the bottom of the grill, you must trim enough to give them room to clip. You have 2 adjuster screws, 1 for vertical 1 for horizontal. Since the stock lamp is 6.75" & the new is 7.0" the adjusters are out of the stock bucket area, so you have to make holes in the flat part of the grill for the adjusters. A little tricky, but you can't see them unless your looking for them. Paint the buckets flat black as they are bronze new. A small portion of the bucket can be seen through the grill.
OK, wiring. The plug for the back of the lamps is the standard 3 wire plug. Looking at the back of the lamp you have 3 tabs on the bulb.
12 O'clock is the low beam. Yellow
3 O'clock is the ground. White
9 O'clock is the high beam. Brown
The left side fog plug:
Blue with black stripe is "+"
Black is "-"
The right side fog plug:
White with red stripe is "+"
Black is ground.
Cut the male end connector off of each Hella wiring lamp harness so you have 3-4" of wire on each female connector
Each new H-4 lamp has 2 connections that go to the stock fog harness. You will connect the low beam to the "+" side & you will connect the ground.
The stock relay for the fogs should be adequate for the 80w low beams. The circuit also has a 15 amp fuse so the fuse will blow before any damage can happen to the harness. If I find the relay is insufficient I will then wire a separate unit, but I do not for see it.
Now for the high beams. The Hella relay has 4 connections:
# 85 is ground
# 30 is 12 volts "+" in.
# 87 is out to the lamps.
# 86 is the 12 volt "+" trigger.
I ground (85) the relay to where I mount it. This way it is a short wire. I used one of the studs that hold the horn bracket to the radiator support for the mounting. Use the one behind the support.
I got my 12 volt "+" (30) from the fuse & relay box by the right side headlamp. Pull the cover & you will see a bolt in the back that holds a cable supplying power to the system. Unbolt the bolt & attach a wire eye connector.
To trigger the relay (86) I picked up the high beam circuit off of the right side headlamp. The white wire is the hot side for the high beam. This way whenever you put on your high beams or flash other vehicles all four lamps come on at the same time. No need for extra switches in the car.
The (87) connector then goes from the relay to the brown wire of each Hella lamp harness.
I put all of the wires into a 3/8" black wire loom, tape & wire tie everything up & it looks like it is factory.
It is not hard, just time consuming. You will find this the be the best $100 you can spend on your car.
Find your favorite wall or road & beam them as you like. I hope this will help some of you guys & gals out. Enjoy
I have gotten a few requests already so here is the supplier of the lights & air horns. I have no affiliation with them.
Classic Garage
997 Route 6
Brewster, NY 10509
845-940-1900 Mon-Fri
Ask for Stewart or Tim & tell them that the Pony Express referred you about the 05' Mustang Fog Conversion.
You want the 2 lamps & buckets, comes assembled. Golf II
2 80-100watt H-4 Super White bulbs
1 Hella fused relay
2 Hella lamp wire connectors
#27
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Originally posted by RRRoamer@April 6, 2005, 7:12 PM
Pony Express,
Approximately what does this cost in parts? I think I have a LOT more use for driving lights than I do for fog lights in my part of the country.
Pony Express,
Approximately what does this cost in parts? I think I have a LOT more use for driving lights than I do for fog lights in my part of the country.
This is the best money I have spent on my car.
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Thanks. I think this may be the next mod I do to my car. I FINALLY installed the Eibach Pro springs in my car (had them for almost two months...). Love them.... Next project please!
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Pony,
I see why you wired your lights the way you did. I finished the physical installation of the lights this weekend. Things hit a big snag when it came time to wire them. All because Ford decided that fog lights shouldn't be on when the high beams are on.
My original plan (forgetting that the fogs are always off when the highs are on) involved using one relay triggered by the fog light power to send power to the lights and a seperate relay with both a NO and NC connection to turn on the high or low beam driving lights depending on if my high beams were on or not. Real easy. Except that the driving lights would always be off when I had my high beams on...
Next plan: Find out were the high beam/fog light power is switched so I can tap it BEFORE it is turned off with the high beams. Oh wait. Electronic car. That is all done in the "smart module". Scratch that.
Third plan: Tap right into the fog light switch and use that to drive the relay. A quick review of the fog light wiring diagram showed the probem with that: the fog switch simply pulls a high signal low (by grounding it) when you trun the fog lights on. This is just an input port to some kind of IC. No high current and the logic is reversed (12V is OFF and 0V is ON). Scratch this idea too!
Fourth plan: Use a 4011 NAND gate tied to the fog light switch and the flash to pass switch. The output will drive a transistor that will send power to the fog light relay. I will power the circuit from a switched accessory lead so it will always be off if accessory power is off. The nice thing about this is that I have full control over my driving lights(on/off, high/low) using the factory switches so I can select high beams without having my driving lights on.
The downside is that I have to build this little circuit, find the wiring from the fog light switch and the flash to pass switch AND find an accessory lead to power it all. Plus, I have to run a low power wire from my interior all the way to the front of my car were my relays are mounted (or will be at any rate!). I'll probably mount the transistor on the relay as well so that I only have to have one very small wire going to the front.
What a pain in the tail. All because Ford decided fog lights should always be off if the main lights are on high. Probably some Federal law requiring it...
I see why you wired your lights the way you did. I finished the physical installation of the lights this weekend. Things hit a big snag when it came time to wire them. All because Ford decided that fog lights shouldn't be on when the high beams are on.
My original plan (forgetting that the fogs are always off when the highs are on) involved using one relay triggered by the fog light power to send power to the lights and a seperate relay with both a NO and NC connection to turn on the high or low beam driving lights depending on if my high beams were on or not. Real easy. Except that the driving lights would always be off when I had my high beams on...
Next plan: Find out were the high beam/fog light power is switched so I can tap it BEFORE it is turned off with the high beams. Oh wait. Electronic car. That is all done in the "smart module". Scratch that.
Third plan: Tap right into the fog light switch and use that to drive the relay. A quick review of the fog light wiring diagram showed the probem with that: the fog switch simply pulls a high signal low (by grounding it) when you trun the fog lights on. This is just an input port to some kind of IC. No high current and the logic is reversed (12V is OFF and 0V is ON). Scratch this idea too!
Fourth plan: Use a 4011 NAND gate tied to the fog light switch and the flash to pass switch. The output will drive a transistor that will send power to the fog light relay. I will power the circuit from a switched accessory lead so it will always be off if accessory power is off. The nice thing about this is that I have full control over my driving lights(on/off, high/low) using the factory switches so I can select high beams without having my driving lights on.
The downside is that I have to build this little circuit, find the wiring from the fog light switch and the flash to pass switch AND find an accessory lead to power it all. Plus, I have to run a low power wire from my interior all the way to the front of my car were my relays are mounted (or will be at any rate!). I'll probably mount the transistor on the relay as well so that I only have to have one very small wire going to the front.
What a pain in the tail. All because Ford decided fog lights should always be off if the main lights are on high. Probably some Federal law requiring it...
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Progress has been made. The lights are fully installed and wired with the exception of the control circuit to turn them on. I have temporarily ran a pair of wires to the interior and installed a switch (NO drilling!) so I can have the lights this weekend when I take a road trip.
I thought long and hard on how to wire them up. I tapped power off the main fuse box just like Pony did. I wish Ford would include a couple of spare 30 amp fused leads we can tap into inside the main fuse box. That would make things SO clean! There are a couple of unused fuse spaces, so I may need to look into taking apart the main fuse box and tapping directly into them. But not today!.
I ended up mounting the two relays (on/off and high/low) behind the passenger side main head light. They sit down in the "hole" behind the light and in front of the main fuse box. To keep things looking stock, I built up a wiring harness and wrapped it in the the same type of flex conduit. For the first pass, I attached the harness to the grill insert, but I will eventually go back and move the harness to the radiator support with the other wiring harness that runs across there. It will look even more stock and it will make it easier to remove the grill insert and lights in the future. Even without the radiator cover installed, all the wiring looks very stock.
To get everything working correctly, I needed to tap into the low beam circuit. This is the trigger to turn the driving lights to low beam. I unwrapped the main harness so I could get to the correct wire inside the harness instead of getting it at the pigtail that goes to the light. I cut it and spliced it back together with an extra signal wire, then buttoned it all back up. Very clean. The only way you can tell something is not quite stock is that extra wire that comes out next to the passenger side main light pigtail. It drops down and goes to the relay trigger, so you don't really see it unless you are looking for it.
So, the way things are wired up now, I can have just my main lights on (high or low beam), main lights plus driving lights (also high and low beam on all lamps), or just the driving lights on high beam. Once I have built that interface circuit I talked about a few days ago (the parts came in last night), my lights will be completely controlled with the factory switches. I also need to tap into the factory fog light on indicator light so it powers up with my driving lights. (the indicator light is powered on the ground leg of the factory fog lights, so without bulbs in the stock harness, the indicator light does not come on).
It was worth the work, but definitely work! Not something you are going to bang out in a couple of hours and have a nice job.
I thought long and hard on how to wire them up. I tapped power off the main fuse box just like Pony did. I wish Ford would include a couple of spare 30 amp fused leads we can tap into inside the main fuse box. That would make things SO clean! There are a couple of unused fuse spaces, so I may need to look into taking apart the main fuse box and tapping directly into them. But not today!.
I ended up mounting the two relays (on/off and high/low) behind the passenger side main head light. They sit down in the "hole" behind the light and in front of the main fuse box. To keep things looking stock, I built up a wiring harness and wrapped it in the the same type of flex conduit. For the first pass, I attached the harness to the grill insert, but I will eventually go back and move the harness to the radiator support with the other wiring harness that runs across there. It will look even more stock and it will make it easier to remove the grill insert and lights in the future. Even without the radiator cover installed, all the wiring looks very stock.
To get everything working correctly, I needed to tap into the low beam circuit. This is the trigger to turn the driving lights to low beam. I unwrapped the main harness so I could get to the correct wire inside the harness instead of getting it at the pigtail that goes to the light. I cut it and spliced it back together with an extra signal wire, then buttoned it all back up. Very clean. The only way you can tell something is not quite stock is that extra wire that comes out next to the passenger side main light pigtail. It drops down and goes to the relay trigger, so you don't really see it unless you are looking for it.
So, the way things are wired up now, I can have just my main lights on (high or low beam), main lights plus driving lights (also high and low beam on all lamps), or just the driving lights on high beam. Once I have built that interface circuit I talked about a few days ago (the parts came in last night), my lights will be completely controlled with the factory switches. I also need to tap into the factory fog light on indicator light so it powers up with my driving lights. (the indicator light is powered on the ground leg of the factory fog lights, so without bulbs in the stock harness, the indicator light does not come on).
It was worth the work, but definitely work! Not something you are going to bang out in a couple of hours and have a nice job.
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I kind of figured that after doing some more research and found all kinds of threads on disabling this "feature" on different, newer cars. I wish Ford had done it the way some other companies did: They had a special relay built (with the stock Bosch 5 pin 30 amp relay connections) that basically had two triggers. You pull that "special" relay out and drop in a standard Bosch 30 amp relay and you are rocking and rolling!
Just a quick update, I finally finished beaming the lights and installed the 80/100w bulbs. Very nice. I really like that hard cut off you get with the low beams. It works very well with the stock head lights. Hopefully, I will be able to find and spice into the four wires I need to install my interface chip (fogs on/off, flash to pass, 12V switched power lead and ground lead) under the dash.
I have pretty much decided I am going to trim the legs down on the NAND gate chip (16 pin DIP) and fold the legs under. Then, just solder the wires directly to the legs and wrap it all up in electical tape. Once it is tucked up under the dash, it will be completely invisble. I will also install the transistor across the relay socket for the on/off relay. This way, I only need one small size wire to carry the signal from inside the car to the relays and I MIGHT be able to get everything wrapped up inside the factory wire harness.
I am definitely looking forward to finsihing this up!
Just a quick update, I finally finished beaming the lights and installed the 80/100w bulbs. Very nice. I really like that hard cut off you get with the low beams. It works very well with the stock head lights. Hopefully, I will be able to find and spice into the four wires I need to install my interface chip (fogs on/off, flash to pass, 12V switched power lead and ground lead) under the dash.
I have pretty much decided I am going to trim the legs down on the NAND gate chip (16 pin DIP) and fold the legs under. Then, just solder the wires directly to the legs and wrap it all up in electical tape. Once it is tucked up under the dash, it will be completely invisble. I will also install the transistor across the relay socket for the on/off relay. This way, I only need one small size wire to carry the signal from inside the car to the relays and I MIGHT be able to get everything wrapped up inside the factory wire harness.
I am definitely looking forward to finsihing this up!
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Better late than never they say... !
So here is the update I promised a couple of months ago!. My first rev of the interface circuit was built and installed over Thanksgiving. The lights worked perfectly. Unfortunately, the accessories would not turn off! To make a long story short (you can find a thread on my accessories not turning off in the issues forum if you want), the light circuit was loading down the input to the SJB. This freaked it out enough that it would not turn off the accessories. At all. To the point of draining my battery in about 16 hours... But I had complete control of my lights from the factory fog light switch!
Rev 1 was build and installed today. It works perfectly! Let's see if I can give a fairly clean discription of how this circuit works, starting at the input:
1) The inputs (one for the fog lights and one for the flash to pass) is composed of two 47k ohm resistors. One is the current limiting resistor that goes between the input signal and the input to the CD4012 Quad NAND gate (next item). This just limits how much current can flow to the input. The second resistor is tied right to the input signal and the current limiting resistor. The other end is tied to the accessory 12V feed. It's whole lot in life is to hold the input line at 12V UNLESS the input signal is grounded (which is on for your fog lights and most other circuits in the 05 mustang, buy the way!). When the input signal is grounded, it easily "over powers" the pull up resistor and the signal to the input of the CD4012 drops to ground.
2) The CD4012 is a CMOS Quad NAND (Not AND) gate. Basically, it is composed of a pair of four input NOT and gates. Basically, the output of this device will be high (12V) if one (or more) of the four inputs into it are NOT high. Given that both the fog lights and the flash to pass signals are high (12V) for off and low (ground) for on, this is exactly what you need to turn the driving lights on with either signal.
3) The out put of one of the Quad NAND gates (the other is completely unused by the way) goes through a current limiting resistor and then to the base of a fairly high current transistor (3 amps continous. I only need 0.16A, so it is WAY more than enough!). The immitter of this transistor is tied directly to ground. The collector is tied to the relay coil for the on/off relay and the other side of that relay is tied to 12V (up under the hood).
4) I also installed an LED with it's current limiting resistor as well. It is controled by the transistor in 3) and turns on when the lights should be on. Originally put on there for initial trouble shooting and I didn't see the point of removing it!
So, basically, when the fog light swich is turned on, it grounds the input (both to my circuit AND to the SJB!). The CD4012 then "sees" that all the inputs are not asserted (at 12V), so it turns "off". But because it is an inverting AND gate (a NAND), "off" for it is actually asserted, or 12V at the output!. This signal then turns the transistor on completly into saturation (we are using it as a switch, not a small signal device), so it conducts the collector directly to the emmiter. Because the emmiter is tied directly to ground, this grounds the coil on the on/off relay which turns it on because the other side is wired up to a constant 12V supply!
Power for this circuit was taken from under the center console at the automatic transmission shifter harness. I have a manual, so it is completely unused. It is a switched power source, so when the car is off, there is no way this circuit can be on. Which means there is no way the lights can be on when the car is off.
When everything was wired and tested, I wrapped the small circuit board (1/2 x 1" or so) with electrical tape and then used a piece of double sided foam tape to mount the board to a flat bracket under the dash. Nothing visible. No holes drilled for aftermarket switch. Easy to return to stock. Not sure why I would, but...
Oh, and on the way back home from Thanksgiving at Moms, the lights proved their worth. I was cruising in the country (New Mexico). I had just got around a slower truck and turned my "big" lights on.
And what was standing in the middle of the road up ahead? A deer. She was completely invisible with my regular lights on high, but the second the driving lights came on, she was clear as day. A bit of work with the brakes and she got out of the way with no issues. It would have been a LOT more "exciting" if I didn't have my driving lights that night!
So here is the update I promised a couple of months ago!. My first rev of the interface circuit was built and installed over Thanksgiving. The lights worked perfectly. Unfortunately, the accessories would not turn off! To make a long story short (you can find a thread on my accessories not turning off in the issues forum if you want), the light circuit was loading down the input to the SJB. This freaked it out enough that it would not turn off the accessories. At all. To the point of draining my battery in about 16 hours... But I had complete control of my lights from the factory fog light switch!
Rev 1 was build and installed today. It works perfectly! Let's see if I can give a fairly clean discription of how this circuit works, starting at the input:
1) The inputs (one for the fog lights and one for the flash to pass) is composed of two 47k ohm resistors. One is the current limiting resistor that goes between the input signal and the input to the CD4012 Quad NAND gate (next item). This just limits how much current can flow to the input. The second resistor is tied right to the input signal and the current limiting resistor. The other end is tied to the accessory 12V feed. It's whole lot in life is to hold the input line at 12V UNLESS the input signal is grounded (which is on for your fog lights and most other circuits in the 05 mustang, buy the way!). When the input signal is grounded, it easily "over powers" the pull up resistor and the signal to the input of the CD4012 drops to ground.
2) The CD4012 is a CMOS Quad NAND (Not AND) gate. Basically, it is composed of a pair of four input NOT and gates. Basically, the output of this device will be high (12V) if one (or more) of the four inputs into it are NOT high. Given that both the fog lights and the flash to pass signals are high (12V) for off and low (ground) for on, this is exactly what you need to turn the driving lights on with either signal.
3) The out put of one of the Quad NAND gates (the other is completely unused by the way) goes through a current limiting resistor and then to the base of a fairly high current transistor (3 amps continous. I only need 0.16A, so it is WAY more than enough!). The immitter of this transistor is tied directly to ground. The collector is tied to the relay coil for the on/off relay and the other side of that relay is tied to 12V (up under the hood).
4) I also installed an LED with it's current limiting resistor as well. It is controled by the transistor in 3) and turns on when the lights should be on. Originally put on there for initial trouble shooting and I didn't see the point of removing it!
So, basically, when the fog light swich is turned on, it grounds the input (both to my circuit AND to the SJB!). The CD4012 then "sees" that all the inputs are not asserted (at 12V), so it turns "off". But because it is an inverting AND gate (a NAND), "off" for it is actually asserted, or 12V at the output!. This signal then turns the transistor on completly into saturation (we are using it as a switch, not a small signal device), so it conducts the collector directly to the emmiter. Because the emmiter is tied directly to ground, this grounds the coil on the on/off relay which turns it on because the other side is wired up to a constant 12V supply!
Power for this circuit was taken from under the center console at the automatic transmission shifter harness. I have a manual, so it is completely unused. It is a switched power source, so when the car is off, there is no way this circuit can be on. Which means there is no way the lights can be on when the car is off.
When everything was wired and tested, I wrapped the small circuit board (1/2 x 1" or so) with electrical tape and then used a piece of double sided foam tape to mount the board to a flat bracket under the dash. Nothing visible. No holes drilled for aftermarket switch. Easy to return to stock. Not sure why I would, but...
Oh, and on the way back home from Thanksgiving at Moms, the lights proved their worth. I was cruising in the country (New Mexico). I had just got around a slower truck and turned my "big" lights on.
And what was standing in the middle of the road up ahead? A deer. She was completely invisible with my regular lights on high, but the second the driving lights came on, she was clear as day. A bit of work with the brakes and she got out of the way with no issues. It would have been a LOT more "exciting" if I didn't have my driving lights that night!
#34
Thanks for the highly detailed update, but now my brain hurts. I'm a mechanical engineer, not electrical, so again in simple terms; Your fog lights come on with the normal pull of the light switch and stay on all the time, is that correct? Or do they operate all the time i.e. daytime running lights? Sorry if these questions seem stooopid.
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Any time the fog light switch is on and the vehicle is on (accessories powered) , then the driving lights will be on. If the headlights are also on, then the driving lights will also be high or low to match the main head lights. If you only have the parking lights on (but the fog light switch on), then the driving lights will be on and on high. It works VERY nice!
I'm a ME tool. But I DID spend two years in the EE program (plus I'm an electronics hobbies), so I do at least know my way around a soldering iron!
Now all I have left to do is rewire the fog light indicator light a bit so it is controled by MY relays instead of the factory relay. Without the bulbs installed, the light doesn't come on. Which pisses me off actually! Because the wiring diagram from the factory shows that the fog indicator light is driven by the fog light RELAY, but it actually appears to be driven by the ground through light filiments. I probably just need to put a resistor in the bulb socket so 10mA or so goes through to power the indicator bulb.
If you decide you want to do the driving light upgrade, let me know. I can put together a nice circuit diagram for you that will show you exactly were everything needs to go. There are only 10 components TOTAL (not counting a few jumper wires) and seven of those are resistors! It really is easy to solder up this circuit using a small perf solder board available at Radio Shack. If I was REAL ****, I would spend the $51 bucks and have a three custom made PC boards made up for this. I bet I could make that circuit 3/8" x 3/4" or less in size and there would be no jumper wires required. Hummmmm....
I'm a ME tool. But I DID spend two years in the EE program (plus I'm an electronics hobbies), so I do at least know my way around a soldering iron!
Now all I have left to do is rewire the fog light indicator light a bit so it is controled by MY relays instead of the factory relay. Without the bulbs installed, the light doesn't come on. Which pisses me off actually! Because the wiring diagram from the factory shows that the fog indicator light is driven by the fog light RELAY, but it actually appears to be driven by the ground through light filiments. I probably just need to put a resistor in the bulb socket so 10mA or so goes through to power the indicator bulb.
If you decide you want to do the driving light upgrade, let me know. I can put together a nice circuit diagram for you that will show you exactly were everything needs to go. There are only 10 components TOTAL (not counting a few jumper wires) and seven of those are resistors! It really is easy to solder up this circuit using a small perf solder board available at Radio Shack. If I was REAL ****, I would spend the $51 bucks and have a three custom made PC boards made up for this. I bet I could make that circuit 3/8" x 3/4" or less in size and there would be no jumper wires required. Hummmmm....
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RRRoamer & all interested
Glad you got the lights working, but I think for most folks my way of wiring will be the easiest with just the one relay. The stock factory fog relay seems to be fine for the 80W side.
This will be a great mod for those of you that want the new center grills that are now available.
I may also have a new lamp available shortly. Stay tuned.
Glad you got the lights working, but I think for most folks my way of wiring will be the easiest with just the one relay. The stock factory fog relay seems to be fine for the 80W side.
This will be a great mod for those of you that want the new center grills that are now available.
I may also have a new lamp available shortly. Stay tuned.
#39
<div class='quotetop'>QUOTE(PONY XPRESS @ February 20, 2006, 7:38 PM) Quoted post</div><div class='quotemain'>
RRRoamer & all interested
Glad you got the lights working, but I think for most folks my way of wiring will be the easiest with just the one relay. The stock factory fog relay seems to be fine for the 80W side.
This will be a great mod for those of you that want the new center grills that are now available.
I may also have a new lamp available shortly. Stay tuned.
[/b][/quote]
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RRRoamer & all interested
Glad you got the lights working, but I think for most folks my way of wiring will be the easiest with just the one relay. The stock factory fog relay seems to be fine for the 80W side.
This will be a great mod for those of you that want the new center grills that are now available.
I may also have a new lamp available shortly. Stay tuned.
[/b][/quote]
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