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So to get all the lights on at once, Fogs, Low, and High do we just use
The Alt to Mod 2 diagram ?
OK, I was wrong. Now that I have all 6 lights as HIDs, I do indeed notice that I would benefit from the fogs being on with the highs and lows. The fogs are like filler, and they have a wider spread.
You can install a 3rd relay just like the one on the right in the Alt to Mod 2 diagram. You can jump the same connections that the left relay is jumping to the right relay. The only differences for the 3rd relay would be output pin 30 to the power wire on one of the fog light harnesses, and I would run a separate power wire with it's own fuse to pin 87.
I'm getting ready to do this myself, but I'm trying to think if there are going to be times when I would NOT want the fogs on when the brights are on.
I'm actually thinking of wiring two toggle switches into the ashtray compartment. One would turn off the power going from pin 30 on the left relay to pin 86 on the right relay, which would in effect cut power to the lows when the highs are on, and the other would turn off power from pin 30 on the left relay to pin 86 on the new fogs relay.
This way at the flip of a switch I can shut off lows when highs are on if I want, and 2nd toggle switch would enable me to turn off fogs when highs are on if I want.
Now if there was only a classier way to do this ...
"Get a 6" long wire and in the fusebox, connect the high beam relay signal wire to the low beam relay signal wire, i.e. connect slot #xx to #yy".
Or something in that nature.
there aren't any relays for the high or low beams in the electrical center though. there are fuses, but the power runs through the headlight switch directly without a relay in there. connecting them is a simple way of getting your low beams to stay on when you turn on your high beams, unfortunately it would also make your high beams come on when you turn on your low beams, which is bad. you would have to install a diode to prevent it from going backwards, and it would have to be able to handle a large amount of current. they aren't easy to come by.
if there were relays you could use a diode on the low side of the relay, the signal, since the current flow through those wires is very small. I have been thinking about putting in my own relays since I installed the HIDs to make sure they get enough power. I am doing to do so with the fog lights, but maybe the headlights too eventually. then a simple diode would make the high/low work without any extra relays. the same could be used for the fog lights if they are on a relay also.
also, the tap into the headlight power wire which make the headlights pop up (according to the service manual) is back near the headlight switch. so if you did do this, and you used 2 diodes to prevent current from flowing back to the headlight switch, and to make the high/low work, it very well may solve the headlight pop up during flash to pass problem!
Now if there was only a classier way to do this ...
"Get a 6" long wire and in the fusebox, connect the high beam relay signal wire to the low beam relay signal wire, i.e. connect slot #xx to #yy".
Or something in that nature.
While at first glance, the mod may appear to be unruly, it really is a pretty straight-forward and clean setup. While I chose to mount my relays in the battery compartment right next to the fuse center, I could just as easily have placed the relays somewhere where they wouldn't be seen, but I wanted easy access to them during the experiment stage. I routed the wires in such a way that you don't even notice them, so in the end I ended up leaving the relays right where they are. Besides, that's where the stock fuse center is, so it's probably a good spot for these relays anyway.
Wait a minute! I just remembered, you could go spend $50 in the Eckler's catalog for a relay mod kit they sell, but then you'd have to deal with the headlights popping up during the day when you flash-to-pass. And, that's why I did this mod instead. About $12 for two relays. I already had some wire and connectors. Besides, with my setup I can easily add another relay to keep the fogs on with the brights, too. I feel sorry for the deer that cross my headlights. But, at least now I'll be able to see them from a far distance!
Last edited by MrLeadFoot; 10-12-2007 at 12:52 AM.
I've received alot of interest in my headlight relay mod, so I thought I'd update this thread to include pics on how I did it, as well as where my relays are fitted.
Note that the captions for each pic pertain to this particular diagram:
The pic below shows the tap into the passenger-side headlight harness. I opted to tap here because it was easily accessible which makes it easier to work, and also makes it easier to uninstall, if I ever wanted to. The light-green wire (high-beam) tap runs to pin 87 on the left relay, which we'll call Relay 1, while the tap to the tan wire (low-beam) runs to pin 30 on the right relay, which we'll call Relay 2. The blue wire that you see bypassing the harness connector runs down to the positive wire (I believe it's a tan wire) on the side-marker light, and connects to pin 86 on Relay 1. The black wire you see runs down to the frame rail ground (you can see part of the yellow connector at the frame), and connects to pin 85 on each of the two relays. I temporarily ran all 4 wires along the gap between the coolant overflow tank and the inner fender. (I still haven't gotten around to putting a wire-loom on and routing them permanently, because they seem to be fine right where they are, and I'm probably going to add another relay to also keep fogs on when my highs are on - see below.)
The pic below shows the wires routed up toward the battery compartment.
The pic below shows the relays mounted to the battery compartment divider. At the bottom of the pic note the red power wire attached to terminal B+ of the fuse center. This is where the red wire draws power to power the low-beams when the high-beams are turned on. The red wire is fused and connects to pin 87 on Relay 2. The fuse rating needs to be double the rating of whatever you have in now for one of the low beams. For example, if your driver's and passenger's low beam fuses are each 10 amp, the fuse on the new power wire should be 20 amps.
I'm probably going to add another relay to the mix to keep my fogs on, too, when my high-beams are on, since fogs really do help now that all my lights are HIDs. Below is yet another diagram for that setup. Note that since the stock fog-lights are on a single circuit that only uses a single fuse, the fuse on the new power wire for the fog-lights should only need to have the same rating as the stock fog-light fuse.
If anyone has any questions, please post them here on this thread, because my PM box seems to reach its limit quite quickly, and I'd hate to miss someone's question.
Last edited by MrLeadFoot; 03-26-2019 at 10:35 PM.
I did the three relay mod on my 99.
Prewired the three relays with all the jumpers and then pulled each new wire one at a time....was careful,
BUT I must have messed up because it did not work
This is what I ended up with.
First switch position I get my HID Fogs as before, headlights down
Second switch position, headlight go up, Fogs go OFF, High and Low beams are both ON
Switch the High Beam switch ON I get ONLY HIGH BEAMS, no Low, no Fogs.
Remove the two in line fuses and all goes back to stock.
Wondering if some of the inline taps failed due to the different wire sizes involved.........but some must have made connection as in the Low beam position the Lows and Highs both come on and the Fogs go Off so the relay must ne functioning somewhat.
So before I tear it all out again.........anyone with ideas where I messed up ?
While I have not done the 3rd relay for fogs myself yet, It sounds like you don't have something right even without the fogs.
1) Pull the connections on the 3rd relay, just to get it out of the picture.
2) Now try the highs. Do your lows stay on? If not, it does not sound like you tapped the correct wires, so post EXACTLY which wires you tapped, and to which posts on the relay each tap is connected.
Sounds right, as far as the relays are concerned. But, are you sure you have the lows and highs tapped right? Sounds like you may have those reversed, which may be why when the lows are on, the high beams come on, too.
Sounds right, as far as the relays are concerned. But, are you sure you have the lows and highs tapped right? Sounds like you may have those reversed, which may be why when the lows are on, the high beams come on, too.
OK,
Reversed the High and Low feed at the relays and the Lows and Highs work as desired........so I guess I wasn't as careful as I thought
But the fogs still go OFF when the Highs go ON.... ....I am guessing that the lead from the relay to the fogs is not making contact at the splice at the fog light harness.......so that will be the next location tested
Sounds right, as far as the relays are concerned. But, are you sure you have the lows and highs tapped right? Sounds like you may have those reversed, which may be why when the lows are on, the high beams come on, too.
double check all of your connections. the way the high and low relay mod works is to tap into both the high beams and low beams signal wires. the high beam wire is connected the relay's coil, so the relay is energized when the high beam is on. the wire to the low beams is connected to the contact with the other side a fused hot source, so when the relay is energized it delvers 12V to the low beam wire. it sounds to me like you have those two wires reversed somewhere causing basically opposite behavior.
also if you have a voltmeter use it to test all of your connections. make sure you get 12V where you should when the lights are on etc. nice that when something doesn't work with this mod you can just pull the fuses and be back to stock though!
mcgiles
I did have these reversed (post 34) so the H&L beams not work as desired but I am still losing the Fogs when the H beams are turned on back to the tester...............
mcgiles
I did have these reversed (post 34) so the H&L beams not work as desired but I am still losing the Fogs when the H beams are turned on back to the tester...............
glad to hear, progress is being made. the fog lights are as simple a circuit as the headlights, take a voltmeter to it and figure out why voltage (or ground) isn't going where it should, the problem should present itself!
WOW!! What a great detailed thread!! I recently installed the 6000K HID low beams and double WOW!!!! Too bad I don't have fog lights to convert. Almost never use high beams anymore--and they are now are a bright yellow in comparison to the HID's. BTW, I had (have) no problem with headlight door actuation after install.
As I suspected the splice tap where my 16ga feed wire taps to the Fog's 24 ga power lead did not bite into the Fog's 24ga power lead.........so I had to strip back the fogs Fog's 24ga power lead and tap in old school....thank goodness for low temp solder paste
But I noted that now my right side low beam and fog are the ones that some times do not light the first time..........used to be only the left side low beam ??? Go figure.
So the next light mod will be to run new, heaver guage, wire harnessed to the LB and Fogs......I would post a link, but they are on the bay and that's a
Thanks for all the help guys
One more question.......does anyone think it would be wise to use a one way diode on these feeds to prevent power surging from the HIDs back to the stalk switch ?
10-10-2007, 03:55 AM
