I just noticed that the fog lights on my 2016 Zetec TDCi are not working when I hit some fog and nothing seemed to happen. When I got home, I checked that neither was working (but the rear one is) so started in the obvious way by checking the fuse which is okay. To test the relay, I swapped it with the one next to it (reversing light) and that was okay - so I thought maybe both bulbs had gone, one by one, and I hadn't noticed but I checked the driver's side bulb on a meter and it didn't seem to be blown but for good measure, I tested it on a bench power supply and it worked. When I put a meter on the connector, I couldn't find a voltage.

I don't know where to go from here - if anybody has any ideas I'd be grateful.

15 minutes ago, Tangerine said:

I don't know where to go from here - if anybody has any ideas I'd be grateful.

Does your car have 'auto-headlights' ?

No, just the standard with audible warning.

48 minutes ago, Tangerine said:

the fog lights on my 2016 Zetec TDCi are not working

Just rechecking this, does the Zetec have front fog lights ?  Perhaps @Eric Bloodaxe can confirm ?

 

 

Yes, a Zetec should have front fogs as standard and it sounds as if Alf's does.

 

 

Well, there are fog lights visible on the front of the car. There are two fog light fittings with a fog light bulb in each. There are connectors from the fog light fittings with cables leading (somehow) to a front fog light relay and a front fog light fuse.

13 minutes ago, Tangerine said:

There are connectors from the fog light fittings with cables leading (somehow) to a front fog light relay and a front fog light fuse.

Attached below is the circuit diagram for the front fog lights on a 2016 Fiesta.

They are controlled by the Body Control Module (BCM). There are no relays, and only one main fuse in the battery junction box 125A which supplies many systems, so you would certainly know if that fuse had blown.

Can't think of anything offhand not already mentioned, but to clarify:

1 hour ago, Tangerine said:

I just noticed that the fog lights on my 2016 Zetec TDCi are not working

Have they ever worked previously? Daft question I know, but I rarely used mine (and now Ford have obliged by deleting them from the Mk 8.5 altogether😀).

And further daft question, is the lighting switch "on" for side or headlamps before switching on the fogs?

FRONT FOG LAMPS



Press the control to switch the fog lamps on or off.

You can switch the fog lamps on when the lighting control is in any position except off.

OK I've got a circuit diagram for the OP's car. It must be a late registered 2015 model built to the 2012 specification. See schematic below:

To test that the wiring and fog lights can work simply remove the relay and then using something like a short length of wire, link out terminals 3 & 5 of the relay socket. Both front fog lights should come on.

The fog light illuminated indicator cycles on and off when the button is pressed but only when the main beam lights are on.

I would not swear that I am 100% certain that the fog lights have worked as my previous car was a Fiesta Zetec TDCi so my memory might be a bit blurry.

Thanks for the diagram, it's basically the same as the Haynes manual absent the rest of the lighting. I wondered if it might be fixable with FORScan but the videos I have seen showing the options do not actually have a simple enabling parameter - only options to enable the fog lights on one side when turning and enable the fog lights with full beam (so-called Bambi mode) which would be quite handy where I live as there are a lot of deer.

I haven't used FORScan for a while and last time I did, the licensing server was unavailable due to it being based in Russia and I'm generally Mac based so getting a Windows system up and running to hook up FORScan will be a bit of a faff but it has been on my mind.

2 minutes ago, Tangerine said:

The fog light illuminated indicator cycles on and off when the button is pressed but only when the main beam lights are on.

mmmmm.... that's wrong. The front fog lights should never be able to be on when the main beam (high beam) is on. They should only work with sidelights (now called parking lights) or the dipped beam (low beam) headlights.

If you carry out the relay test, and let me know what happens I can talk you through how to find the fault and most probably fix it.

11 minutes ago, unofix said:

To test that the wiring and fog lights can work simply remove the relay and then using something like a short length of wire, link out terminals 3 & 5 of the relay socket. Both front fog lights should come on.

I'll try that. I did take the fog light relay out and test it in the reverse light relay slot and it worked so I suppose this test would finger either the trigger or power wiring. I had been waiting for the opportunity to ask somebody to push the fog light button for me so that I could listen to the relay but it's a bit remote here and my girlfriend has been out all day so that will have to wait as well.

37 minutes ago, Eric Bloodaxe said:

(and now Ford have obliged by deleting them from the Mk 8.5 altogether😀)

Not to mention deleting the Fiesta altogether.

8 minutes ago, unofix said:

mmmmm.... that's wrong. The front fog lights should never be able to be on when the main beam (high beam) is on. They should only work with sidelights (now called parking lights) or the dipped beam (low beam) headlights.

If you carry out the relay test, and let me know what happens I can talk you through how to find the fault and most probably fix it.

Sorry, different use of terms - I was talking to a Slovakian BMW driver the other day and he said main beam and high beam (I usually say low beam and high beam). But, as mentioned earlier, there does seem to be an option to enable this (high beam with fog lights - Bambi mode) using FORScan.

2 minutes ago, Tangerine said:

there does seem to be an option to enable this (high beam with fog lights - Bambi mode) using FORScan.

Indeed there is but that is not legal for use on public roads in the UK.

7 minutes ago, unofix said:

Indeed there is but that is not legal for use on public roads in the UK.

I didn't know that. I used to use fog lights with side lights to (slowly) drive up a private road near where I live to avoid shining my headlights into somebody's bedroom window but I don't go that way much anymore.

I'd love to be able to try out Bambi mode because deer can appear out of nowhere around here. I imagine it makes a difference if the option is there and people use it.

18 minutes ago, Tangerine said:

I used to use fog lights with side lights to

Again that would now be illegal in the UK and Europe. Back in the day, when side lights were exactly that, you could legally drive with just them in areas with street lighting.

For a good many years now, (possibly 2013?) side lights have been renamed 'parking lights'. The law now states between the hours of Dusk till Dawn vehicles must use a minimum of dipped (low beam) headlights. Also whenever the windscreen wipers are in use, dipped beam headlight must also be used.

34 minutes ago, unofix said:

Again that would now be illegal in the UK and Europe.

I take it you read that I specified driving up 'a private road'.

1 hour ago, Tangerine said:

I take it you read that I specified driving up 'a private road'.

Missed the private bit 🤣

You can even use 'Bambi' mode on a private road 👍

16 hours ago, unofix said:

Also whenever the windscreen wipers are in use, dipped beam headlight must also be used.

Is that in daylight too?  Some new car (LED?)dipped headlights (especially SUV's, 4X4's etc.) can be blinding even in the daytime, especially if it's raining.

I heard /read that there is to be an enquiry into the future use of standard fit high intensity headlights on cars because of the dazzling problem.

 

10 minutes ago, Magenta said:

Is that in daylight too? 

Yes.

Cars that have automatic headlights will turn them on when the wipers are turned on.

https://www.gov.uk/guidance/the-highway-code/driving-in-adverse-weather-conditions-226-to-237#:~:text=Rule 226. You MUST use headlights when,off when visibility improves (see Rule 236).

That should apply to my car then as I have an auto headlight position but don't use it,   although it is useful in multistory car parks for instance.    I'll check the wiper operation.

On a Mk7 Fiesta, both autolights and autowipers need to be selected, and the wipers must be on continuous sweep (due to large amount of rain) for lights to come on during daylight.

Text from Rules 226 and 236:

(When is a foglight not a fog light ? When it is a Cornering Light ?)

Rule 226

You MUST use headlights when visibility is seriously reduced, generally when you cannot see for more than 100 metres (328 feet). You may also use front or rear fog lights but you MUST switch them off when visibility improves (see Rule 236).

Rule 236

You MUST NOT use front or rear fog lights unless visibility is seriously reduced (see Rule 226) as they dazzle other road users and can obscure your brake lights. You MUST switch them off when visibility improves.

Where is the rule about wipers ?  And if the hanbrake is on headlights should go off - I'm fed up with being dazzled by "get you home lighting" and cars parked offside to.