Fog lights don't work. Any help?

Just a shot in the dark--you do know that factory fogs are wired to come on only when low beams are on and no other time, right?

If cleaning up the terminals doesn't do it--here are my thoughts.

How were your HID's wired? If anything were done to divert low-beam switch circuit from the fog relay it might not be coming on. Is there any clicking at the relay when you energize the fog switch with low beams on?

If not, either the relay coil is not getting ground or or not getting 12V+. If the pin-out is on the relay can, you can test to see if there is power and ground at the coil pins and if there is power and load (resistance to ground through the bulbs) at the contact pins. I'd tell you which pins are which, but the on-line wiring diagram is a 2002 with DRL's and that's different and my '99 has aftermarket fogs. (My guess is the coil power is constant, and the ground comes from the low-beam circuit and goes through the fog switch to the relay. On non-DRL 4Runners, the high/low beam circuit is a switched ground. So checking for power at the switch may be useless--it is probably a switched ground. I also don't see anything under the dash that would affect fogs on a truck with no DRL's.)

If the above paragraph is beyond you, then I think you need someone to help.

Here is the 2002 Fog circuit with DRL's, the contact side should be the same. 1 & 2 are the coil pins,3 & 5 are the contact pins.

Linky 2002 FSM Wiring Manual
 
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Just a shot in the dark--you do know that factory fogs are wired to come on only when low beams are on and no other time, right?
If cleaning up the terminals doesn't do it--here are my thoughts.

How were your HID's wired? If anything were done to divert low-beam switch circuit from the fog relay it might not be coming on. Is there any clicking at the relay when you energize the fog switch with low beams on?

If not, either the relay coil is not getting ground or or not getting 12V+. If the pin-out is on the relay can, you can test to see if there is power and ground at the coil pins and if there is power and load (resistance to ground through the bulbs) at the contact pins. I'd tell you which pins are which, but the on-line wiring diagram is a 2002 with DRL's and that's different and my '99 has aftermarket fogs. (My guess is the coil power is constant, and the ground comes from the low-beam circuit and goes through the fog switch to the relay. On non-DRL 4Runners, the high/low beam circuit is a switched ground. So checking for power at the switch may be useless--it is probably a switched ground. I also don't see anything under the dash that would affect fogs on a truck with no DRL's.)

If the above paragraph is beyond you, then I think you need someone to help.

Here is the 2002 Fog circuit with DRL's, the contact side should be the same. 1 & 2 are the coil pins,3 & 5 are the contact pins.

Linky 2002 FSM Wiring Manual

I do know the fogs only come on with the low beams. But with my HIDS only having low beams it shouldn't be a problem, correct?

As far as everything else it is way above me. My uncle is the auto mechanics instructor at the local technical college so I may just ask him to explain it to me. Thanks for trying though! I really do appreciate it.
 
I do know the fogs only come on with the low beams. But with my HIDS only having low beams it shouldn't be a problem, correct?

As far as everything else it is way above me. My uncle is the auto mechanics instructor at the local technical college so I may just ask him to explain it to me. Thanks for trying though! I really do appreciate it.

Did you at least try the click test??

I can tell you this. On my '99 with no fogs, the relay socket is set up like this--I just looked (Looking at it over the driver's fender):

--
-- | |
--
The coil is between the two vertical tabs on the right. The switch contacts go from top left to bottom left and close when the coil is energized.

Putting labels on the pins:

--12V+ from FOG fuse, powers on with low-beams
-- Not used |12V+always on |ground from switch
-- Out to fog lamps

First check and see if you have 12V+ at the top left with low-beam on. If not, problem is probably with FOG fuse. If you do have 12V+ there, jump the top left pin slot to the bottom left pin slot and fogs should come on. If not, problem is with the lights themselves or their connections.

Then check if you have 12v+ in the left hand pin slot of the pair on the right. I'm not sure where this 12V+ comes from, but you need it. Finally, you should have ground in the far right pin slot with fog switch on and low-beams on. That ground should become an open when fog switch is turned off. If not, problem is in the switching circuit.

Is that better? :)
 
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Was wondering how this ended, I just installed mine and they are not working either but I think its in the daytime running light module as I can jump mine at the relay and make the fogs come on. I'm not getting a ground at the relay, not too concern as I can bypass the Daytime running module if needed.
 
I was to. I am trying to get mine working. Fuse is good, bulbs are good, but I don't have the inside light on the switch coming on? Not sure why it is not coming on but I am chasing it down.
 
I was to. I am trying to get mine working. Fuse is good, bulbs are good, but I don't have the inside light on the switch coming on? Not sure why it is not coming on but I am chasing it down.

Resurrecting an old thread once again but did you ever figure this out mforce?

I installed the dealer-optioned Hella lights on my 98. Took everything right out of another 98 that had the option from the dealer, I took the lights, relay, fuse, and switch straight out of the truck I have not changed any of the connections so I know the wiring is correct. I did have to disconnect the switch to run the wires through the firewall and I thought I connected them the same way but I can't get the light to come on the switch or the lights themselves.

The picture below is how I hooked up the switch (purple is the ground). I put a new fuse in but I have not replaced the bulbs - I don't think that would stop the light from coming on the switch would it?

Anyone have any insight? Could it be a bad ground, I thought I did a decent job grounding it.
 

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Gotta touch base on this!

Resurrecting an old thread once again but did you ever figure this out mforce?

I installed the dealer-optioned Hella lights on my 98. Took everything right out of another 98 that had the option from the dealer, I took the lights, relay, fuse, and switch straight out of the truck I have not changed any of the connections so I know the wiring is correct. I did have to disconnect the switch to run the wires through the firewall and I thought I connected them the same way but I can't get the light to come on the switch or the lights themselves.

The picture below is how I hooked up the switch (purple is the ground). I put a new fuse in but I have not replaced the bulbs - I don't think that would stop the light from coming on the switch would it?

Anyone have any insight? Could it be a bad ground, I thought I did a decent job grounding it.

Ok I hate to really open up this thread again but I am having the EXACT same issue. I am working on a 1997 with the factory/dealer installed FOGS in.
I have replaced the rusty HELLA relay. Found one online and NAPA and replaced the 15 amp fuse. The moment I put the fuse back in, i can hear the relay clicking. GREAT! Go to the switch which is also factory installed with the orange light and nothing. No light no nothing.
The wiring is Black (ground) top, Purple in the middle and yellow at the bottom. I cannot figure it out. Anyone, please let me know.

Thanks
 
Hello, I bought an 06 SR5 4Runner Saturday. I am liking it alot but the fog lights don't work. I checked the bulbs & fuse. I don't have an independent switch should I?

I'd appreciate any help thanks.
 
Hello, I bought an 06 SR5 4Runner Saturday. I am liking it alot but the fog lights don't work. I checked the bulbs & fuse. I don't have an independent switch should I?

I'd appreciate any help thanks.

You should really try the 4th gen forum. This is for '96-'02. Factory wiring changes a lot between generations. It's like posting about an e36 cabrio in an e30 forum.

4th Gen T4Rs - Toyota 4Runner Forum - Largest 4Runner Forum
 
Fog Relay

I just recently bought an 02 SR5 which came with the factory fogs, but they do not work. I checked to make sure the fuse is good inside the cab and it is good. However the relay is missing under the hood, does anybody know which specific relay I need?
 
I just recently bought an 02 SR5 which came with the factory fogs, but they do not work. I checked to make sure the fuse is good inside the cab and it is good. However the relay is missing under the hood, does anybody know which specific relay I need?

Stock p/n is 90987-02012, updated to 90084-98031, which a dealer will sell you for over $50 without lube.


RELAY | Genuine Toyota | 90084-98031



Or this puppy from NAPA p/n ECH AR614 made by Echlin will do fine for $15 and change:

https://www.napaonline.com/napa/en/p/ECHAR614/ECHAR614_0235386227

Do you have the stalk switch?
 
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No I don't believe I have a switch for it, I assumed they just come on with the low beams.


Sent from my iPhone using Tapatalk
 
Thanks a lot for the info on the relay!


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Resurrecting this. My fogs aren't working either. I can hear the relay click when turning the switch on and off. When checking for power on the relay socket I DO have power at the top left pin w/ the low beams on. However I don't have any power at the left hand pin slot of the pair on the right. Anyone know where that 12v comes from. Any ideas of anything else to try?

I used my power probe on the wires at the fog lights themselves. Both wires are showing ground. When I apply power to the red wire the lights come on.

Did you at least try the click test??

I can tell you this. On my '99 with no fogs, the relay socket is set up like this--I just looked (Looking at it over the driver's fender):

--
-- | |
--
The coil is between the two vertical tabs on the right. The switch contacts go from top left to bottom left and close when the coil is energized.

Putting labels on the pins:

--12V+ from FOG fuse, powers on with low-beams
-- Not used |12V+always on |ground from switch
-- Out to fog lamps

First check and see if you have 12V+ at the top left with low-beam on. If not, problem is probably with FOG fuse. If you do have 12V+ there, jump the top left pin slot to the bottom left pin slot and fogs should come on. If not, problem is with the lights themselves or their connections.

Then check if you have 12v+ in the left hand pin slot of the pair on the right. I'm not sure where this 12V+ comes from, but you need it. Finally, you should have ground in the far right pin slot with fog switch on and low-beams on. That ground should become an open when fog switch is turned off. If not, problem is in the switching circuit.

Is that better? :)
 
Resurrecting this. My fogs aren't working either. I can hear the relay click when turning the switch on and off. When checking for power on the relay socket I DO have power at the top left pin w/ the low beams on. However I don't have any power at the left hand pin slot of the pair on the right. Anyone know where that 12v comes from. Any ideas of anything else to try?

I used my power probe on the wires at the fog lights themselves. Both wires are showing ground. When I apply power to the red wire the lights come on.
Which year and do you have DRLs?

-Charlie
 

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