Fog Light Frustration

[weekendclimber]

So, I've always battle with my fog lights on my 1999.5 SR5 3.4l V6 4x4. After busting a lens on one many years ago and just taking them off, I just recently purchased a set of Hella Micro DE to replace them both. Since all the wiring was good to go, I just got the pair of lights without the wiring kit and switch.

Anyway, long story short, I got them setup no problem and then they stopped working after about 2 weeks. Took them off and they had water in the housing and a burnt out bulb. Dried them out, sealed up the housings better, checked all the fuses and reconnected them, but they still won't light back up. Did a continuity check on both the lights and the engine bay fuse block and everything checked out. Still nothing. There is no longer any voltage coming through the connecting wires. Thought I'd share with all ya'll just to see if anyone else has some advice.

Here's the OEM wiring from the FSM (note: I do not have DRLs):

Here's is what I believe my setup is wired as. I do not have DRLs and there has never been a fog relay in my engine fuse block (note: I left out the fuse and wiring that goes to the switch light because I don't believe it has issues):

I've checked that power is coming into the fuse at the start of the chain (Blue-Orange wire), though not after the switch (pink wire, and my shitty red drawn on addition) izza:

Engine bay fuse box from FSM (for reference):

My Engine bay fuse box (note: there has never been a fog relay were the blank spot on the right is):

Cab switch (note: lights up, unless fuse is pulled, see next picture):

Kick panel fuse box (note: the funky looking fuse in the upper left, when pulled, the light on the switch goes out):

So, I've check the engine bay fuse and it's good to go and receives power when check for continuity (at ~12v). Is it possible that there is another fuse along the line that might have blown?

The wiring to the front looks as though it is the OEM wiring and is attached into the main harness up front along with the parking lights and turn signals. According to the wiring diagram, there is not another fuse. Although, the switch to the kick panel is obviously not original, so maybe there was one added?

Could the short have melted a wire? I just don't think that's possible. It's driving me :crazy:

 

[Jc12]

your 15amp fuse on the very bottom left of the box in the engine bay is good?

 

[weekendclimber]

That's correct. Been thinking about just running new wires to the front, but if I can save some work that would be great. Gonna check the continuity after the switch this weekend when I can do it during daylight.

 

[TheDurk]

Well, the first question I have is did the installer put these in with no relay? The add-a-fuse tacked on to the ECU-IG fuse in the box by driver's knee is big enough to power the lights so he may in fact have done that. Running full fog light voltage through a dash switch is not a good idea and tells me it might make sense to rewire the whole thing to include a relay.

Do your fogs come on independently of the headlights, high, low or off, as long as the key is on? If so, that would confirm there is no relay in the circuit. If they are tied to the headlights, that means there is an add-on relay somewhere (probably on the fender) and you need to find it to troubleshoot this system.

Point of info: The dash switch is NOT factory. Factory fog on a '99 used a switch built in to the stalk but the SR5 did not always have fogs. Mine doesn't. So all the wiring from the add-on fuse to the switch up to the tap to the factory pink wire in the engine bay is amateur work. Might be good, might be bad, but it is not factory.

What continuity check did you do in the engine bay fuse block? There is nothing there to check, is there? If there is, you would want to check if there is voltage coming from the red wire that comes from the dash switch where it taps the pink wire going to the lights. Can you locate this tap?

How are you checking voltage at the lights? Are you using battery ground or the ground wire in the harness? If the latter, you also need to verify if the ground side is good.

I help a lot of people on here with electric. But I can't do anything unless I am told EXACTLY what terminals were checked how. You need to be more specific.

In any case, this circuit needs a relay.

Forgive me, but I'm not sure a continuity check is what you think it is.

http://en.wikipedia.org/wiki/Continuity_test

 

[weekendclimber]

First, let me give a big thank you for taking the time to respond with such great detail to my admittedly lackadaisical post :hippie:

Well, the first question I have is did the installer put these in with no relay? The add-a-fuse tacked on to the ECU-IG fuse in the box by driver's knee is big enough to power the lights so he may in fact have done that. Running full fog light voltage through a dash switch is not a good idea and tells me it might make sense to rewire the whole thing to include a relay.

These were installed prior to my acquiring of the rig, but according to the service history on the Toyota website they were installed at a dealer (listed as LAMPS/SWITCHES). I might give them a call today, because when I try to look at the detail online there's an error on that one particular item. I would think that the dealer would do it right, but who knows.

Do your fogs come on independently of the headlights, high, low or off, as long as the key is on? If so, that would confirm there is no relay in the circuit. If they are tied to the headlights, that means there is an add-on relay somewhere (probably on the fender) and you need to find it to troubleshoot this system.

That's is correct: whether or not corner lights or the headlights (low or high) are on, these will come on with a flip of the switch. One note though is that my headlights stay on once I remove the key from the ignition until I open the drivers side door, but the fog lights would turn off when I turn the key to anything other than the "On" position.

Point of info: The dash switch is NOT factory. Factory fog on a '99 used a switch built in to the stalk but the SR5 did not always have fogs. Mine doesn't. So all the wiring from the add-on fuse to the switch up to the tap to the factory pink wire in the engine bay is amateur work. Might be good, might be bad, but it is not factory.

This is exactly what I was thinking, but from what I can tell they were installed at a st(d)ealership.

What continuity check did you do in the engine bay fuse block? There is nothing there to check, is there? If there is, you would want to check if there is voltage coming from the red wire that comes from the dash switch where it taps the pink wire going to the lights. Can you locate this tap?

What I've checked is just the "from power source" spot at the engine bay fuse block so far. The light comes on when I attach the clip of my tester to the engine block and touch the tip of the tester (see image below) to the right-hand leg of the fuse connector in the engine bay marked "FOG" (15Amp fuse). The light on the switch works just fine, so I haven't checked anything in the kick panel, as I assumed (wrongly?) that it's all good there. I believed that that fuse (in the kick panel) is only for the indicator light on the switch, but you have made me realize that this assumption could prove to be false.

How are you checking voltage at the lights? Are you using battery ground or the ground wire in the harness? If the latter, you also need to verify if the ground side is good.

This is a very good point that I missed: I have just checked the former at this point. I will check the latter as well.

I help a lot of people on here with electric. But I can't do anything unless I am told EXACTLY what terminals were checked how. You need to be more specific.

I really appreciate the help. I've done some wiring stuff in the past, but admit to being an amateur at this. Hopefully the above mentioned checks are a little more specific as to what I've checked (which admittedly is not as thorough as needed). I'm using a voltmeter and one of these:

In any case, this circuit needs a relay.

Forgive me, but I'm not sure a continuity check is what you think it is.

Continuity test - Wikipedia, the free encyclopedia

No offense taken and I'm now leaning much more to the side of rewiring this whole thing more to factory :cheers:

 

[TheDurk]

First, let me give a big thank you for taking the time to respond with such great detail to my admittedly lackadaisical post :hippie:



These were installed prior to my acquiring of the rig, but according to the service history on the Toyota website they were installed at a dealer (listed as LAMPS/SWITCHES). I might give them a call today, because when I try to look at the detail online there's an error on that one particular item. I would think that the dealer would do it right, but who knows.



That's is correct: whether or not corner lights or the headlights (low or high) are on, these will come on with a flip of the switch. One note though is that my headlights stay on once I remove the key from the ignition until I open the drivers side door, but the fog lights would turn off when I turn the key to anything other than the "On" position.



This is exactly what I was thinking, but from what I can tell they were installed at a st(d)ealership.



What I've checked is just the "from power source" spot at the engine bay fuse block so far. The light comes on when I attach the clip of my tester to the engine block and touch the tip of the tester (see image below) to the right-hand leg of the fuse connector in the engine bay marked "FOG" (15Amp fuse). The light on the switch works just fine, so I haven't checked anything in the kick panel, as I assumed (wrongly?) that it's all good there. I believed that that fuse (in the kick panel) is only for the indicator light on the switch, but you have made me realize that this assumption could prove to be false.



This is a very good point that I missed: I have just checked the former at this point. I will check the latter as well.



I really appreciate the help. I've done some wiring stuff in the past, but admit to being an amateur at this. Hopefully the above mentioned checks are a little more specific as to what I've checked (which admittedly is not as thorough as needed). I'm using a voltmeter and one of these:

No offense taken and I'm now leaning much more to the side of rewiring this whole thing more to factory :cheers:

Good answers. So at the lights, check the hot lead against battery ground and the ground lead against battery positive to nail down which side is bad. We need to get those lights to come on before we can rewire them, if that is what you want to do. If the ground tests good, I'd jumper 12V from the battery to the pink wire to see if the fogs come on as a test.

I suspect the factory FOG fuse is not wired to anything. If he was powering just the indicator light I doubt he would have used the add-a-fuse. That's why I asked if there was anything to check. The factory set-up takes that fuse straight to the relay contact, and there is no relay. So I figure it dead-ends there.

To go factory, you would have to replace your stalk switch and install the relay in the fuse box. This will be very hard to do without knowing exactly how the dealership put this system together, especially whether they hid a relay under the dash or on the fender or elsewhere.

My personal choice would be to use the dash switch to control a relay on the fender that is powered from the battery for the lights using an in-line fuse. Then run new wires to your fog lights. This is how I added lights to my rig back in '99 and, except for one dead relay about three years ago, it has worked fine ever since. If you prefer to use the existing harness, you can do that, if you can find where the dealer connected the dash switch to the light harness--the red to pink splice in your diagram.

 

[Ol'Blue]

I'm glad that I'm the only one that is having issues fixing my fog lights. I got so pist at mine I just thew all my tools back in the box and walked away.

Is there a diagram some place that should have it all so I can take another stab at it.

Blue

We will get it at some point.

 

[weekendclimber]

Got it. I'm going to check those front wires properly. I bet that there is probably a relay somewhere that I haven't been able to find that's probably toasted. What I'm thinking of doing is moving it into the engine bay fuse block if that's the case, just to make it easier down the road. What I'm thinking is wiring it up as follows:

Does that make sense?

Going to figure out that switch and stuff this weekend.

 

[weekendclimber]

I'm glad that I'm the only one that is having issues fixing my fog lights. I got so pist at mine I just thew all my tools back in the box and walked away.

Is there a diagram some place that should have it all so I can take another stab at it.

Blue

We will get it at some point.

I'm using the diagram in the FSM on page 1955. My 99.5 doesn't have DRLs, so it's a little different, but obviously these were not factory installed. In essence, that wiring diagram is totally useless...:wacko:

 

[TheDurk]

Got it. I'm going to check those front wires properly. I bet that there is probably a relay somewhere that I haven't been able to find that's probably toasted. What I'm thinking of doing is moving it into the engine bay fuse block if that's the case, just to make it easier down the road. What I'm thinking is wiring it up as follows:

Does that make sense?

Going to figure out that switch and stuff this weekend.

Well, it's probably easier to ground the switch inside the cab and tap a 12V source for the coil in the engine bay. That way you can have it come on only with parking lights, or low beams, or however you want. This is the way the factory fogs are wired.

I don't like posting diagrams for relay circuits because there are many ways to make it work, and a diagram shows only one.

 

[TheDurk]

I'm glad that I'm the only one that is having issues fixing my fog lights. I got so pist at mine I just thew all my tools back in the box and walked away.

Is there a diagram some place that should have it all so I can take another stab at it.

Blue

We will get it at some point.

I can't tell you how to wire it (or post a diagram) unless I know how you want the lights to behave (anytime, key on only, with parking lights only, with low beams only), stalk switch or dash switch, truck with or without DRL's, and factory relay or add-on relay.

Start your own thread if you really want help.

 

[weekendclimber]

Well, it's probably easier to ground the switch inside the cab and tap a 12V source for the coil in the engine bay. That way you can have it come on only with parking lights, or low beams, or however you want. This is the way the factory fogs are wired.

That makes sense. The way I'm going to set it up is to have it function the way it did before all the current problems (on with switch, no matter if parking, headlights, etc. are on). I'll basically move the switch to the other side of the coil. Would you recommend fusing the 12v source for the coil?

I realize you don't like posting diagrams, but thought I'd just throw another one out there to make sure I'm on the right path (I'm keeping these for future reference so I don't have to do any guess work in the future):

 

[TheDurk]

Normally you don't need a fuse for the source for the relay coil because you tap into some specific existing circuit (parking lights, low beams, ignition) to allow control of when they come on. It's really easy to come home after a rain shower when the sun has come out and forget to turn off the fogs. The coil drain is really small and a separate fuse is not called for.

But yeah, otherwise looks good. I don't mind approving one for a specific use.

EDIT: Well, if you want it the way it was before, use the red wire off the add-a-fuse as the 12V+ source to the switch, run the switch wire to one side of the relay coil and then ground the other side of the coil near the relay. That will keep the fogs off when the key is off, but able to come on any other time.

 

[IBallEngineer]

I'm glad that I'm the only one that is having issues fixing my fog lights. I got so pist at mine I just thew all my tools back in the box and walked away.

Is there a diagram some place that should have it all so I can take another stab at it.

Blue

We will get it at some point.

Don't lose it!! My good friend [MENTION=10169]TheDurk[/MENTION] will help you out, or if he's busy I can give you my $.02 as well.

Seriously though, this shit is easy! Piece of cake, cup of coffee, walk in the park, slam dunk, no sweat!!

 

[weekendclimber]

Well, the first question I have is did the installer put these in with no relay?

So, I had a chance to take a better look at this today, and low and behold, there was a hidden fuse and relay tucked in next to the battery. I did check everything else in my final wiring diagram, but am going to hold off wiring it all more to factory at a later date.

The add-a-fuse tacked on to the ECU-IG fuse in the box by driver's knee is big enough to power the lights so he may in fact have done that. Running full fog light voltage through a dash switch is not a good idea and tells me it might make sense to rewire the whole thing to include a relay.

Looks like that add-a-fuse was indeed just for the light power.

I appreciate the direction on getting this figured out. It's kind of fun looking at all the wiring diagrams. Having wired tons of guitar effects and roady rigs for different bands, its got me wanting to do more custom lighting on my rig:hungry:

 

[weekendclimber]

Does anyone else use the Hella Micro DEs? It seems like I keep blowing fuses with them because they end up getting water inside the housings. I've got the plastic backing piece on there properly and have added a tight fitting band around where it overlaps the housing. Not sure what I can do to make them more watertight. You can see how they are sealed in this picture(note: these are not my Hellas but are representatve):

 

[weekendclimber]

I do see this post: http://www.toyota-4runner.org/3rd-gen-t4rs/152077-hella-micro-de-foglight-problems.html

Going to go the extra mile to seal these up a lititle better and see if that helps...I might be talking to myself here :dammit:

 

[weekendclimber]

Here's how I'm sealing them up now. I've got RTV on the holes that the wires come out, zip tied the rubber boot to the housing and 1/4" plastic hose in the drain hole that is zip tied up high inside the engine bay. We'll see if that pops any fuses now op2:

 

[Unner]

Hopefully that solves your issues. I'm hoping I won't have issues like this with the OEM fog lights that I have on the way...

 

[weekendclimber]

Just an update: clamping the rubber boots, RTV'n the wire outlet holes, and running a tube from the breather hole up into the engine compartment seems to have done the job. I haven't had a problem in the last couple weeks at all and it there were a couple or real rainy days up here in Seattle. I'm sure everyone watched the Seahawk's battle back in the last quarter against the Packers...well I was driving around that day and it was WET!!!