Rear Fog wiring...anyone? (1 Viewer)

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Rear fog lights should only be used in bad weather. If you have them wired to the tail lights then they're on whenever your lights are on - bad idea.

Those are LED more for esthetic view. Definitely not as bright as OEM outside US
 
I managed to install the rear fog lights this weekend. Since my car was not pre-wired, I had to use a separate switch and relay. Still a work in progress. I plan on using the factory euro stalk with the rear fog light switch which means I will also need a latching relay because the rear fog switch on the stalk is momentary contact. I have a latching relay on the way, I'll need to figure it out first before I commit to buying the stalk.

Also take note that the wire harness listed in this thread is for cars without rear sonar. If you have rear sonar, you need a different harness. I highly recommend getting the harness. It's expensive but worth it. Everything snaps into splace, looks factory and makes the job a lot easier.

7/8" or 22mm hole saw is the perfect size to drill the hole

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Photo from the net that I used as reference for where to cut the notches
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More photos. I decided to do dual rear fogs instead of just one on the left side because the 2017 models here come with dual rear fogs standard.

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Update:

I took a peek inside the cluster and discovered that there is no LED for the rear fog indicator. I'm going to have to solder a LED in there and see if it lights up when I ground pin 9 of connector E2 on the main body ECU.


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I also purchased the correct rear fog light housings. The reflector inside the rear fog housing is shiny chrome versus the matte chrome finish on the stock "reflex reflector". The result is a slightly brighter output

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Stock reflex reflector on the left, OE rear fog housing on the right. The right is just slightly brighter
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A couple more photos...

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I don’t think any US variants have this. I have my 2009 LX bumper cover off right now. Definitely no wires there just the passive reflector. It would be a cool mod though.
 
E2 Pin to grond works for light the cluster ?

Yes that's what is says in the rear fog light wiring diagram I attached a few posts back. Ground signal from the rear fog light switch goes to pin 9 of E2 connector on the body control unit and triggers the dash light via CAN. However, there are two possible problems:

1. If there is no LED in the cluster like in mine, it obviously will not light up. Solution is to solder a LED in there.

2. Even with the LED installed in the cluster, dash light might not light up due to different body control unit hardware/software. Solution is to solder a wire directly to the negative lead of the rear fog LED and have a relay ground it when the rear fog is activated

I don't have any LEDs laying around so I'm still unable to do this. I had to buy a used cluster from another Toyota vehicle off ebay so I can get the LED from it (I don't want to use cheap Chinese LEDs from ebay ;)). When it arrives I will give this a try
 
Oh please , yes let me know ! Another question can you post a picture of the location of the e2 conector ? Thanks

E2 connector is the 28 pin plug on the body control unit. On a LHD vehicle it is above the kickpanel and behind the left hand side switch panel where the mirror switch is.
 
Got it , thanks

Let us know if grounding pin 9 of E2 on your car lights up the dash light. Front fog light must be turned on for the rear fog light to trigger

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Update:

I got the rear fog stalk. This is from a Toyota GT86 and is plug and play with the 2008-2015 200 series with power tilt/telescopic steering wheel. Both LC200 and GT86 rear fog stalks were available locally but I got this instead because it's half the price of the LC200 one, and I prefer the Auto function to be the first one triggered like in the 2016-up 200 series.

I also got the latching relay and was able to test it on the bench. Works great. The latching relay I got is from a BMW Z3. Now all that's left is to solder the LED in the cluster.

Part number of the LHD Toyota 86 rear fog stalk is SU003-02473

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Top: GT86 stalk
Bottom: 200 series stalk
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Finally finished this project. Rear fog light stalk and dash indicator light are fully functioning. Once I soldered the LED and reisistor on the cluster, grounding pin 9 of connector E2 triggers the indicator light. Unfortunately, there was no output from pin 14 of connector E3 of the body ECU which is supposed to trigger the rear fog relay. So I had to use a bunch of relays along with the latching relay to get it to work

UPDATE: turns out pin 14 of connector E3 does output a negative trigger for the rear fog. So I ditched the latching relay and just used a regular SPST relay wired as follows:

85 connect to pin 14 of E3 connector
86 to +12v from TAIL or FOG
87 +12v output to rear fog bulbs
30 fused +12V


Here's a video:



Spare clusters for parts
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E2 connector with wire attached to pin 9 which triggers the dash indicator

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Yellow LED and 680 ohm resistor from donor FR-S cluster. The circuit board provides +12 volts to the LEDS - the resistor is installed on the negative side of the LED
 
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Finally getting ready to move forward on retrofitting rear fogs. Looked up the previously sited p/n on PartSouq and this appears to be the current list (see below). The only hang up I’m having is sourcing the wire harness. It’s not coming up when I enter it. I contacted PartSouq and they’re saying they can’t get the harness p/n based on my VIN (no s***, my 2014 LC didn’t come w/rear fogs) but might be able to if I give them a VIN from a vehicle that did come equipped with them.

Any thoughts on figuring out a current part number for the harness?

Lens, Rear Fog Lamp 8145660031
Lens, Rear Fog Lamp 8145760021
Cover, Fog Lamp (x2) 9007599080
Bulb (x2) 9098113043
Switch Assy, Headlamp Dimmer 8414030311
 

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