Adding fog lights but switch does not work

[Tobata_Nagata]

i am in the process of adding fogs to my 2016 se. i have switched the setting in FORscan, and installed a headlight switch that includes the pull out for the fog lights. my issue is that the switch after plugging it in, not only does it not turn on the fogs when pulled out but the lights stay on no matter the switch position. I am thinking the switch is just bad somehow but i thought id ask the experts, have any of you guys experienced anything like this?

 

[Frine]

I haven't but plan to install fogs in my car as well. I'll let you know how it goes and if anything similar happens.

 

[Handy Andy]

Does this Color Code and wiring match what you have?

Switch wiring to BCM


Fog Lamp Relay Switch to BCM and Fuse block wiring
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Wait...there's more!
This is the one that shows the FUSED output from the RELAY box - to the lamps themselves...
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There is a set of two fuses and the wiring needed to support the lamps as a Fused output from the Fusebox in the engine side...

That's why I asked about your wiring and color code - you'll have to track down this to trace the wiring and make sure you have the support for it.

Please take a moment to review your wiring and make sure you have the wiring correct.

The last graphic, is more for the European models - but you may find the wiring color code matches this - as in one Fog light wire is Yellow Grey, but REQUIRES a fuse to be installed at the location F35 to complete the circuit for it.

But the differences are at PIN 14 of the BCM - or the FOG light wire at the switch - it's color code is Violet WHITE or Violet GREY - two colors that are different, but are SHADES of each other - both use the same pin, but have different outcomes.

Else you'll have to make your own relay and harness for it - the FOG light switch itself just needs ground to make the relay coil side energize so the relay contacts can switch the load. The BCM is or should be sent up already for this.

 

[Tobata_Nagata]

I don't believe that my wiring has the same color code as the diagram you provided, below are some pictures of the harness from behind the fog light switch. at the moment I'm just wondering why the new headlight switch wont even turn on the headlights, would not having the correct wiring and fuses effect this?

 

[Handy Andy]

In fact, it is, refer back to the PINOUT numbering of those wires---

I've just matched them for you in the Pin out of the connector.

You have all the wires needed to the switch...

Here ya go!

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The only difference is BLACK Yellow is used for both grounds...which Black Yellow and Black Green and Black Blue are all Grounds to chassis (Bolted to the body, you can measure this ohmically 0Ω to the frame of the vehicle to verify)

 

[Tobata_Nagata]

That's great thanks so much! so I should be good to go with the fog lights without having to add fuses or having to do any wiring as long as i have the fog light setting FORscan activated. I think the reason why the headlights dont work with the new switch is the used switch i bought off ebay is just not working.

 

[Handy Andy]

You will still need two fuses 1 at F36 and 1 at F35 - both are 10A (Red) each - that takes the output of the Relay and fuses it before it goes to the Fog lights.

Verify the color code of the wiring back at the fuse box - one wire Left - should be "Lemon - Blue stripe" color - Right hand is Blue - Brown stripe color these are the output to the Fog lamps to power them from the fuses - so check the F36 and F35 spots and ohmic-check them for continuity to the Fog light connector end at the lamp.

 

[Tobata_Nagata]

according to the user manual f35 and f36 are the "Stability assist/anti-lock brake system valve" and the "starter motor solenoid" There are however f48 and f49 which are labeled right and left fog lamp respectively, they both already have 10a fuses installed from the factory. is that what you are talking about?

 

[Tobata_Nagata]

i just tested it with a newly fixed headlight switch and everything works just as it should! Thanks again for all of your help!

 

[Handy Andy]

according to the user manual f35 and f36 are the "Stability assist/anti-lock brake system valve"

Thanks, for the various years, one schematic does not fit all.

But I'm also glad to know...

tested it with a newly fixed headlight switch and everything works just as it should!

The main area of concern was to make sure you had all the wires to the switch. You showed that with the photos. Just sorry the eBay version of the switch was faulty - not good for them, though.

In my experience - most (not all - Trim lines take precedent due to their Body Control Module amd VIN) Fiestas already have their wiring installed for much of their trim lines - they just don't install the electronics unless you pay separate and can "fiddle" with features using FORscan. It's dangerous ground to some - but the simpler installs like this and turn signal light valence on the side mirrors - you can do, but it takes knowing that the wiring harness for the mirror will have to be added to, but the wiring support at the connector in the door where it meets the main harness branch - does have the wiring up to that connector - you can upgrade the mirror using a junkyard or other aftermarket or Ford direct-itself - depending on the ease of the install you want it to be - just be ready to pay $$$ for it.

Due to the upgrade to SYNC, changes to the SRS (Air bag or Bang - system) and trim features - each year beyond a given wiring schematic - will have the additional support and fuses - subsequently added and numbered incrementally to a point where you have nearly 100 fuses in some vehicles - with each little module or featurette - fused separately.

IT can be a nightmare - just glad this one was just a needed switch.