Installing Rear Fog/Chase Light Using Factory Switch & Harness

[4x4TruckLEDs.com]

These do not work

I purchased these from my front fogs and tried the connector is not the same.

I would be willing to send the connector I cut off to someone who makes harnesses to help find a correct one though.

Send me the connector.

4x4TruckLEDs.com
190 E Hoffman Ave
Unit B
Lindenhurst, NY 11757

Just put a note in the package with your user name on here. If we have a harness already made (because we have other harnesses for Fords) we'll send you one free. If I have the connectors in stock (because we also stock misc. connectors) Il'l make you a free pigtail

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[ksmich]

I did my rear fog install today. I installed the factory Rear Fog Harness (M2DZ-15K868-G*) in the bumper. I also installed the Front/Rear fog switch (M2DZ-11654-CB) in the dash.

To connect to the rear circuit I crimped on a 2 pin Deutsch connector and built a harness to distribute to the lights.

I used the low power circuit (R/W wire on rigid Harness) for the Fogs with plans to connect brake lights to the high power (Red wire on Rigid Harness) for now I just stubbed it out, but I would change the Deutsch to a 3 pin if/when I do it.

Ran my custom harness along the factory harness to both sides of the bumper.

Links to all parts:

https://parts.ford.com/shop/en/us/parking-distance-aid-sensor-wire-14758343-1?pdp=y

https://parts.ford.com/shop/en/us/headlamp-switch-14868567-1?pdp=y

https://www.rigidindustries.com/sr-q-series-diffused-rear-facing-high-low-sm-red-set-of-2-90163.html

https://www.4x4truckleds.com/kr-off...ount-light-for-ditch-light-a-pillar-brackets/

https://www.deutschconnectorstore.com/deutsch-dt-series-connector-kits.html

 

[WheelMe]

Very nice, someone's actually done it! Thanks for posting.

I'd like to install a pair of rear fog lights, and already have the dash switch installed (though I haven't attempted the rear fog FORSCAN reconfig.). In regards to the M2DZ-15K868-G* harness - I'd need to order one, and how does that connect to the existing tail light harness? Or does it? I'm not sure where that piece falls in your setup. Thanks.

 

[ksmich]

Very nice, someone's actually done it! Thanks for posting.

I'd like to install a pair of rear fog lights, and already have the dash switch installed (though I haven't attempted the rear fog FORSCAN reconfig.). In regards to the M2DZ-15K868-G* harness - I'd need to order one, and how does that connect to the existing tail light harness? Or does it? I'm not sure where that piece falls in your setup. Thanks.

I've been trying to find time to tackle this for everyone and finally did. I hope this can serve as the base of a write up for everyone, I don't have much experience making write ups but I will try my best.


To enable and utilize the factory fog light harness these are the steps needed. You will need ForScan (obviously but had to clarify) and the headlight switch of your choice, mine specifically is the auto lamp one with spot light buttons and just the single fog light in the center of the dial (I forget the part number if anyone knows)

Connect to the vehicle and go into configurations --> BdyCM and open it.
You will want to find and change the following:

Front fog lamps - change this from "Disabled" to "Enabled".
Fog Lamp Switch - change this to "Enabled"
Using Front Fog With High Beam - This is an optional change but if you want to use fogs with high beams change it to "Allowed"

Write the settings made, you are finished with the BdyCM for now

Next you need to open the IPC which will turn on the fog light indicator in your gauge screen:

Front fog lamps - change this to "Enabled"

Write this setting and now we will go onto the As-Built change.

You will need to open BdyCM (As-Built Configuration). BACK UP THIS FILE in case anything goes wrong you can restore the original.

Locate the following line:

726-42-01-xxxx-xxxx-xxxx (My Badlands specifically was 726-42-01-0000-0000-0575)

You will need to change the second box to 0101. ForScan does autochecksum calculations so what I ended up with was 726-42-01-0000-0101-0577

Write this change


I originally started with just the first two parts but while the indicator would show up on the dash I was not getting power to the fog light harness in the bumper. I was curious and compared to a 2021 F-150 spreadsheet. This 726-42-01 is the control line for what the Left and Right fog light circuit actually does. There's a few options but the default setting is "not used". The setting I changed it to (01) is "Fog cornering" (I assume 04 for Fog Only will work too) but there is another one (05) which basically turns that circuit into an always on 12v. The switch does not turn it off and while I tested it with the vehicle on I forgot to check it with the vehicle keyed off though I assume it would be a key on only setting. I mention this just because it could be useful to somone here who may not be hooking up fog lights but might want a low amp, I believe the fuse is only 5 amps, source for other accessories.

For those curious here is the full list of options but I only tried the two I mentioned:

LF_Fog_Lamp_Ckt_Usage_Cfg: 00=Not Used 01=Fog Cornering 02=Fog DRL 03=Fog DRL Cornering 04=Fog Only 05=Power Supply



Also, I did not research or attempt anything relating to the Rear Fog Lamps. I know some people here are seeking that but unfortunately I didn't dive into that yet.

The Rear Config is almost the same as the front just another DID, I found this on another thread.

as for the harness it replaces the factory harness for the bumper (not the tail light). the body harness to the rear is wired (at least on mine it is) to connector C424.

I suppose one could add a pin to the bumper harness that comes from the factory
with terminal EU2Z-14421-BA. and use the shared ground with the license plate light. Driver side bumper connector.

 

[Crash98]

Can I wire rear bumper lights directly to the white/blue wire to have them come on with the rear fog light switch? Or should I use a relay with the white/blue wire as the trigger?

 

[ksmich]

Can I wire rear bumper lights directly to the white/blue wire to have them come on with the rear fog light switch? Or should I use a relay with the white/blue wire as the trigger?

It really depends on your application. It is 18 GA wire so you are limited in how much current you can pull. I have the Rigid SR-Q Low beams (2) tied to the factory wiring and have had no issues. one could probably get away with 5 amps of draw, but its very situational.

 

[Crash98]

It really depends on your application. It is 18 GA wire so you are limited in how much current you can pull. I have the Rigid SR-Q Low beams (2) tied to the factory wiring and have had no issues. one could probably get away with 5 amps of draw, but its very situational.

Thanks. That was my concern. Its a pair of diode dynamics ssc2 sport lights. I decided to go with a relay and use the white/blue wire as a trigger.

 

[WheelMe]

Thanks. That was my concern. Its a pair of diode dynamics ssc2 sport lights. I decided to go with a relay and use the white/blue wire as a trigger.

Please post how your install goes. I'm planning on just one rear fog light, but it'd be nice if I could add some amber chase lights and not blow a fuse.

 

[Crash98]

Please post how your install goes. I'm planning on just one rear fog light, but it'd be nice if I could add some amber chase lights and not blow a fuse.

Will do. PNW rainy season started in full force, so just need to find a dryish day to do the install of new bumper and lights.

 

[WuNgUn]

There shouldn't be any mystery. It goes all the way to the connector in the DS corner of the rear bumper, which also feeds the license plate lamp. And it should not matter what trim - my little ol' base had the white/blue wire for the rear fog circuit.

I used it the other day to wire in an actual fog tail lamp (not OE, but in OE position). I'm probably one of the few who want that instead of using the feed to power rear-facing white lights, but so be it.

As for a spare light mount, I'm happy with the unit I purchased from ACFabb, but I wired the flood lights I have on that to the AUX switch run in the cargo area. One benefit to that - I can switch them on so long as the ignition is on; the rear fog circuit seems to require ignition and headlamps are on.

I'm not a gambling man but willing to bet you have the rear fog circuit going into the DS corner of your rear bumper. Pretty certain all Broncos built thus far do. Doesn't appear to be trim/ option/ market-specific from what I've seen in the service information. Pretty easy to check by crawling under the bumper and looking at that connector.

What fog tail lamp did you use?

 

[etmccaus86]

What fog tail lamp did you use?

https://www.amazon.com/gp/product/B09FF4QPJZ/


EDIT: pic of it installed. Not a perfect install on my part but I'm happy with the result, especially at night.

 

[ChipM]

So I am late to the party too but like everyone am disappointed that the upgraded mod bumper deletes fog lights on the standard switch. As I move forward with all of this and begin my order(s) I have a question about the "G" harness. How do you determine what models have this? I am an OBX Squatch with tow and LUX package.

Also I am terrified of FORSCAN so I am looking for anyone in Northern VA who has exp with this and is willing to offer up help. I am willing to pay for service. If this is you PM me.

 

[ksmich]

So I am late to the party too but like everyone am disappointed that the upgraded mod bumper deletes fog lights on the standard switch. As I move forward with all of this and begin my order(s) I have a question about the "G" harness. How do you determine what models have this? I am an OBX Squatch with tow and LUX package.

Also I am terrified of FORSCAN so I am looking for anyone in Northern VA who has exp with this and is willing to offer up help. I am willing to pay for service. If this is you PM me.

None of the trucks in North America Come with one. you can verify by either looking at the Driver side harness connector for the blu/wht wire. you can also look above the hitch (or where the hitch would) be for a small connector. but unless you have a factory Rear fog you do not have the G Harness.

 

[Crash98]

Got the rear bumper pods wired up and tested out today and everything works great They were Diode Dynamics SS3 pods mounted in the bumper. I wanted to be able to turn them on and off with the rear fog light button on my light switch. I ended up using a 4-pin relay. I used the rear fog light wire, blue with white stripe in driver's side door channel, and tapped that for the relay trigger. ran the light power wires up the driver's side frame into the engine bay. Grounded the lights on the bumper and grounded the relay in the engine bay. Enabled rear fogs with Forscan and it works the way I wanted.

 

[ChipM]

So you were able to link to the rear fog light sitch/button without the "g" harness or is the mythical blue and white wire in the "g"harness?

Sorry all of these posts are confusing me as to what is and isnt here already.

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