fog light -> headlight concerns

Haha nice. I take the time to do the research for you and you are still coming back with comments. When I said I assume, I was stating I assume it is on the back as the fsm does not say which side it is on. But like i said the relay is there. The 4G comment was to assist you in carrying the mod forward to the 5G. I was stating that the 4G had a fog relay but that it was not located in the driver junction box (its in the engine compartment jb). I was THE first person on any web forum anywhere to perform the fog mod on a 3G 4Runner 10+ years ago, I took that knowledge and applied it to the 4G. Perhaps you can learn from others and put a little effort in and get the mod to work on a 5G, but maybe not.

Last time I am going to state this here, the 5th gen does have a fog lamp relay, period.

This place is really unbelievable currently. Maybe I should just post things like "do a search yourself" on every post like most people are doing now a days.
Have a great holiday.

sorry I got defensive with you, but your post said "I hate when people post like that" in response to me asking you a question. I was looking for an answer, not an attitude. and the reason I asked was because my Tacoma had the fog relay in the engine compartment box, whereas the 4R does not. And i checked the box in the cab and it wasn't there either. As you can see, I was looking into this back in June. Thanks to your post, and Nashmans diagram, I think now that it's in the kick panel.

again, sorry I took your post the wrong way.

Happy Holidays.
 
sorry I got defensive with you, but your post said "I hate when people post like that" in response to me asking you a question. I was looking for an answer, not an attitude. and the reason I asked was because my Tacoma had the fog relay in the engine compartment box, whereas the 4R does not. And i checked the box in the cab and it wasn't there either. As you can see, I was looking into this back in June. Thanks to your post, and Nashmans diagram, I think now that it's in the kick panel.

again, sorry I took your post the wrong way.

Happy Holidays.

Not a problem. To clarify, when I said "I hate when people post like that" what I was trying to convey is that i cannot stand it when people post information that they are not sure about. I would never post like that, and though I dont have a 5G I did my research before posting to attempt to assist others as I love the "Fog Mod" and hope others can enjoy it as well. Again, I hope you are successful with this mod on your vehicle. Good luck.
 
the 5th gen does have one for fog, one for hi beams a one for low beams. If you want to see the EWD, just click on the link in my sig. Enjoy :cheers:

Wow! There is a ton of information in here!! I only wish I knew exactly what I'm looking at. I understand most, but am still somewhat confused on exactly where to run a jumper wire, ect to make the fog lights independent from the headlights. I am sorry for sounding naive and kinda dumb here, but can someone point out exactly which relay to modify and how? I'd be eternally grateful!

Also looking to do the 12v mod as well (giving the 12v outlets full time power regardless of whether or not the engine is on). Anyone know which relay this is as well? Thanks!! :thumb3:
 
Wow! There is a ton of information in here!! I only wish I knew exactly what I'm looking at. I understand most, but am still somewhat confused on exactly where to run a jumper wire, ect to make the fog lights independent from the headlights. I am sorry for sounding naive and kinda dumb here, but can someone point out exactly which relay to modify and how? I'd be eternally grateful!

Also looking to do the 12v mod as well (giving the 12v outlets full time power regardless of whether or not the engine is on). Anyone know which relay this is as well? Thanks!! :thumb3:

Has anyone else tried performing these modifications? Still looking for a little help, if someone knows which relays I need to modify. Thanks fellas! :bigok:
 
I'm also interested in this mod. I did a similar mod on my last vehicle and it was nice to have but I gave the 5gen 4r some thought and realized that the fogs are right next to the DRLs. So if you turn on the DRLs and the fogs at the same time without the headlights I feel that might look pretty weird. Just my opinion. It would be interesting to actually see this mod done.

Note: if you have your headlights on the DRL are off and only function as signals.
 
I'm also interested in this mod. I did a similar mod on my last vehicle and it was nice to have but I gave the 5gen 4r some thought and realized that the fogs are right next to the DRLs. So if you turn on the DRLs and the fogs at the same time without the headlights I feel that might look pretty weird. Just my opinion. It would be interesting to actually see this mod done.

Note: if you have your headlights on the DRL are off and only function as signals.

You are absolutely correct. As I do quite a bit of back country night time driving, my goal with this modification was to be able to hit the high beams and maintain the fog lights. Not only provides better visibility for the driver, but useful light right in front of the vehicle.
 
Ahh... Yes you're right forgot about that. When you turn on your High beams the fogs go out. All the more reason to have this mod done. Thanks for the reminder.
 
So I see a lot of people are interested in doing this, but can anyone point us in the right direction with the relays? :hungry:
 
So I see a lot of people are interested in doing this, but can anyone point us in the right direction with the relays? :hungry:

Found this after looking some more (this was how I performed the modification in my 4thGen). Any idea if it is similar on the 5th?
 
I have been wanting to control my factory fog lights separately also so I looked finding this dang elusive fog relay myself today.I couldn't find it either!! Doh!
According to the manuals and looking up under the dash......It seems the fog relay is different then the 4th Gen in that it is housed inside what they call the Main Body ECU.

The Main Body ECU is a little black box up under the drivers side dash. From what I saw and it comes out as a unit and the relay is probably inside as there is a pretty big wiring harness plug going to it.

Help!!!! To all you wiring diagram reading Spark Chasers.....From the factory wiring diagram,page 233
What does the shaded gray area mean,what does FFGO mean coming off the ECU and why does it seem like the tail light activates the fog relay???

I'm going to look into it again tomorrow night to see if I can pull that main body ecu out to find the relay.

I may just wire up my own relay on it's own circuit and switch for the fogs like I did for my PIAA fogs.I have some pre-wired Bosch/Tyco relays just lying around not being used anyways. I'll just pull the 15 amp fuse for the factory fog circuit, as I did find that up under the dash, and be done with it.
 
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I have been wanting to control my factory fog lights separately also so I looked finding this dang elusive fog relay myself today.I couldn't find it either!! Doh!
According to the manuals and looking up under the dash......It seems the fog relay is different then the 4th Gen in that it is housed inside what they call the Main Body ECU.

The Main Body ECU is a little black box up under the drivers side dash. From what I saw and it comes out as a unit and the relay is probably inside as there is a pretty big wiring harness plug going to it.

Help!!!! To all you wiring diagram reading Spark Chasers.....From the factory wiring diagram,page 233
What does the shaded gray area mean,what does FFGO mean coming off the ECU and why does it seem like the tail light activates the fog relay???

I'm going to look into it again tomorrow night to see if I can pull that main body ecu out to find the relay.

I may just wire up my own relay on it's own circuit and switch for the fogs like I did for my PIAA fogs.I have some pre-wired Bosch/Tyco relays just lying around not being used anyways. I'll just pull the 15 amp fuse for the factory fog circuit, as I did find that up under the dash, and be done with it.

From a quick glance, the FFGO is the front fog wire, and the 13 (2D) refers to it's pin location in the connector, as referenced in the 2D pdf from nashman's resource. The actual relay appears to be in something called "Driver Side J/B Assembly Inner Circuit".

Edited to add:
Okay, so I approached it from the angle of having to troubleshoot non-working foglights. Based on the manual's troubleshooting and repair steps, the "Multiplex network body ECU" houses the relay and if it goes bad, you replace the whole ECU, not the relay.

You may find it is one sealed unit with no accessible parts to swap out.
 
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Based on the manual's troubleshooting and repair steps, the "Multiplex network body ECU" houses the relay and if it goes bad, you replace the whole ECU, not the relay.

You may find it is one sealed unit with no accessible parts to swap out.

Ut-oh! That would really stink as I loved the added light ability on my 4thGen (and 3rdGen)!
 
So has anyone figured anything out on the fog relay situation? It looks like this is going to be a real PITA. As Gary mentioned, the easier way may just be to wire up a relay and run it to an external switch... :bash:
 
I looked for the fog relay as I stated before. Toyota changed the way they do most of the relays now compared to the last Gen 4Runners. They are now modular with the relays inside them and not plugged in with prongs like we've grown accustom to.

So the only way I saw around it, without dissecting the modules(they look to be sealed), is is just hard wire my own relays in with a separate switch to switch the fogs on separately. Pulled the oem fog fuse to nullify that circuit.

The Philips 5k HID lights that I had in my fog lights already had their own relay and fuses anyways so it was pretty easy to do for me. I just had to wire a switch from my Painless fuse box to activate the relays. I bought some Carling V switches and mounted them in the dash and wired them up.

Alot of wiring as the switches take 5 wires each because of 2 separate light circuits even though I did set up a grounding point inside. BTW ,an easy way to run wires thru a firewall is use the existing hole with rubber grommet on the drivers side.I learned from an old timer years ago,To get the wires thru .....use a cheap bic or similar pen body ,the kind with the removable ink stick, take the back little cap off,push it thru the rubber grommet right alongside the wires/cable going thru,remove the ink stick from the inside and then pen body is hollow to feed the wire thru ,then go back inside and pull the wire thru and the pen body. Easier then trying to get a wire thru that tight grommet or making a new hole and sealing.

Here's some pics ,I put in a new switch for the compressor while I was at it.

These are the modules the relays are now housed in, up in the drivers side dash.There are 3 separate modules housed inside that bigger module there and the one up to the right is the TPMS ECU

Picture006-5.jpg~original


Wiring to the back of the Carling V switches
Picture005-5.jpg~original


I relocated the dash dimmer switch down with the rest of the OEM switches.
Picture008-3.jpg~original


Out yesterday with just the oem FOGS on.
Picture001-5.jpg~original
 
Great writeup Gary! I had a feeling it was going to come down to this. Next time I have the front bumper off, this is what I'll do. Thanks for all the research and awesome job with the clean install. :hatsoff:
 
Harper
what philip HID lights did you use in your fog lights again? The gx and 4runner have the same fogs which turn off with high beam on.
which one is the oem fog fuse?
 
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^ the reason Harper did it the way he did is the 5th gen doesn't have the same fog relay as older 4Runners. so the link you posted, with the method most people know for the mod, will not work on this generation.
 

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