Fog Lights Installed and Working 4 Non Touring

First let me give credit to sttkailua for starting down this path. While I was considering posting in the original thread 2016 OEM Fog Lights Arrived! | Page 3 | PriusChat
I decided that I may diverge a bit here so I might as well start a new thread.

I bought the fogs from Toyota Online Parts




My first concern was figuring out the wiring but Toyota made it so easy. There are three wires- one for the fog, one for the drl and one for ground. Figuring out the color code was simply looking at the PCB







Green: Fog
Black: Ground
Blue: DRL

Determining the pins on the connector now become extremely easy






Before I installed these, I wanted to make sure passing 12V though the circuit worked.


DRL success




Fog success




There was a lot of talk about the upper screw and how to screw it in. I spent a few hours on this actually. The first attempt was to attach the screw to the screw driver and approach from the top






I could get my arm in from the top and start screwing in but I did not make much progress because the screw driver had a hard time fitting and I was doing it blind




Finally I was done with screwing around and popped the bumper cover. Anyone who has any experience with Toyota knows that with some unbolting the sides pull out. I did not have to remove the entire bumper cover, just enough to pop the sides. Plenty of room, all screws 100% secure








Fogs in





Now about the wiring. The bad news: the head light circuit is active for regular DRL use. They are just running dimmer than usual. This means that you cannot tap the DRL circuit because an 87a relay will not allow the switch. In light of this I decided to give myself full control via a on-off-on switch from the cabin. The wiring will be in such a way to allow the fogs on, the drls on or both off- and that power will be cut when the car is off.


I mounted the switch where the tire pressure switch used to be in the Gen 3. It is out of the way and I don’t might drilling into the plastic. As I had no free buttons anywhere I had to go this route.




Now how did I get the wires into the engine bay? This will be a little hard to explain but just like when installing fogs on the gen3, you have to pierce a grommet. There is one up under the dash that transfers some wires. Here is a slightly blurred picture with the hanger I was about to shove through



Surprise! Hanger in the engine bay





Secure some wires to that hanger and pull them in




The wires going through the grommet (it is two walled so pushing the hanger through you will feel a pop then a pop






The wiring to the switch. I will attach a wiring diagram that will explain why there are 3 power wires and no grounds and how I did this






Then I put her all back together, the red wire hanging will be explained, the other two went into the engine bay





Here is the wiring diagram for how I ran this



Success! Kind of-

I ordered the right connectors and female pins but for the time being I had to wire up a very fragile connection. Two of the connectors are touching accidentally so it is powering both the fog and the drl at the same time in both switch positions. Turning the car off or moving the switch to the center position kill everything as it should. When I get the right connectors in, the system will work 100% and not activate both…. This is just a side effect of things shifted, not the concept. Now that I know it works, I am going to leave the circuit off until the rest of the parts arrive.






Total cost of harness:

$3 switch
$30 14 awg wire (I bought black and red 100ft each might be overkill)
$5 fuse splitter
$14 ebay for the three connectors and 12 female pins (just incase)

Misc electrical take and some wire ends I jimmy rigged the system with.

 

I believe the official Toyota part number for the terminal used in the connector is:
82998-12440

The connector is
90980-10942

These are currently unconfirmed part numbers but I will have them in hand within a few days to validate

 

the problem is if you use power from the battery directly then you need to activate it by a relay or else it will always be activated even when the car is off- dead battery. If you use a relay you need something under control to pull it in. The automatic headlights could have done the trick, however, its the same circuit used for the headlight drls so actually the circuit is always activated.

So this means that you would need to pull the coil of the relay in with some power so that the relay could then flow the power from the battery to the fogs and drls. And now you get into the same situation: what power would you be in control from inside the cabin that can pull in the coil to allow the battery power to flow? There is nothing, if you tap a power source and send it through the firewall than it is the same as what I just did.

I ended up tapping the power outlet aka cig lighter feed. I figure that it is designed in such a way to expect someone to be using it at all times when the car is on- many people plug in a radar detector, phone, gps, etc. for the constant draw. Sending it through the firewall? eh. no choice here

 

If you need to pop the side out, the only hidden screw is where the bumper cover contacts the quater panel. There is a screw that connects the two of them behing the plastic wheel well cover. If you take the clips off the wheel well you can pull the cover away to get to the screw.

 

The fogs will be activated at all times becausenthe headlight circuit is activated at all times when the car is on. This is because the standard drl without fog is a reduced headlight. This would lock you into fog at night and day and while they will power off when the car is off they do not solve the drl control unless you also wire them to the headlight at which point they both will light up at all times with no real control except if you turn the headlights/drl off directly from the stalk or turn the car off. Is that really better?

 

diagram

 

well it appears that the back of the fog\drl housing is printed with 12V 5 Watt. 10 Watt would be about 1 amp I do believe.
In my setup taking power downstream of the power outlet, it is projected by the power outlet fuse, though no fuse in the system is 1 amp. Worst case, fogs blow up but car circuit is protected.

 

Which were you thinking or is there a third setup?

1
Run two 87a relays. One would have the fogs wired to the normally opened and the other would have the drls wired to the normally opened? flipping the switch in the cabin would pull in the relay of one of the corresponding 87a relays which would then carry the voltage from the battery to the fog or drl

2
Or is your idea to have the drls wired to the normally closed and the fogs wired to the normally opened. When the cabin switch is at rest, the DRLs would be on. When the cabin switch is set to the fog then the fog would activate and the DRLs would turn off. In this set you could do this with a regular on-off switch and a single signal wire going into the engine bay but it would be mandatory drl or fog at all time.

 

Here is the enhanced wiring diagram to include two 87a relays. The NC contact will not be used. The NO contact on one will be split and sent to the fogs. The NO contact on the other will be split and sent to the DRLs. The 12V + from the battery will be run through a 10amp fuse and split to go to both commons of the 87a relays. When either relay pulls in, it will transfer the battery power from the common pin to the NO pin activating either both fogs or both drls. The coils of the relays both - will be joined and sent to a ground point (not the negative battery terminal). The + for the coil will be driven off the 12v power outlet tap running through the on-off-on switch in the cabin.

The relays I ordered are mini 87a automotive relays:
Beuler 5083PWMR 12 VDC Micro 5-Pin Relay SPDT

Does this make sense? Are there flaws in the logic?

 

great! thanks for your input on this. The confusion came in when I wasn't visualizing!