Rear Fogs not working

rayfenwick · Post by **rayfenwick** » Wed Nov 03, 2010 1:59 pm

Hi all. Just noticed the rear fogs aren't working. It's not the bulbs, and the contacts in the holders look ok, so where to check next. As it is both sides I'm guessing there's a relay somewhere - unless Citroen decided to save £1 and wire directly to the switch?

As always, all help gratefully received.

Post by **Tim Leech** » Wed Nov 03, 2010 2:47 pm

Switch or fuse?

rayfenwick · Post by **rayfenwick** » Wed Nov 03, 2010 3:53 pm

I swapped the switch, same result, though the other switch is untested.

Fuse... I've not found (or in fairness looked for....) the fusebox yet. :S

I'm guessing that's a "no" to the relay then?

kiwi · Post by **kiwi** » Wed Nov 03, 2010 7:14 pm

Fuesbox is located under the dash in the passenger footwell.

Rear Fogs position F10 and is 5 amp rated.

Post by **Defender110** » Wed Nov 03, 2010 7:26 pm

Come on Ray,. . . . .an electronics guru hasn't checked the fuse

electrokid · Post by **electrokid** » Wed Nov 03, 2010 8:55 pm

Take the NS rear light cluster off - switch on the rear fogs - then wiggle the wires and connectors.

rayfenwick · Post by **rayfenwick** » Wed Nov 03, 2010 10:02 pm

Defender110 wrote:Come on Ray,. . . . .an electronics guru hasn't checked the fuse

Well.. in fairness I did mention that in my first posting, not that I hadn't thought of it.

I thought I'd ask from those who've trod the path before me - prior knowledge can often save a lot of faffing about with a multimeter....

I'll check fuses and do some waggling as suggested and get back to you all. At least there's no relay involved

citronut · Post by **citronut** » Thu Nov 04, 2010 7:59 am

does the rear fog indicater lamp light, if it does it aint the fuse,

also you know they only work with dip beam,

regards malcolm

kiwi · Post by **kiwi** » Thu Nov 04, 2010 8:37 am

citronut wrote:also you know they only work with dip beam,

Wrong!!!

If you are talking about the ph2 BX. Either that or I got two BXs here with a fault that allows them to work

electrokid · Post by **electrokid** » Thu Nov 04, 2010 9:12 am

Wrong!!!

If you are talking about the ph2 BX. Either that or I got two BXs here with a fault that allows them to work

Different countries have different regulations for fog lamp use and wiring. In the Uk it's only legal to use front foglights during 'fog or falling snow' and (certainly in the past - not sure about now) there are regulations governing the wiring to prevent them being used on their own.

It should be from the sidelight circuit - the original idea - and use - of foglights was to reduce 'backscatter'. Normal headlights will illuminate the fog immediately in front of the vehicle - and it's more difficult to see through illuminated fog.

The idea of having a flat beam prevents this illuminated fog getting in the way of seeing clearly in these conditions so the ideal in a pea-souper is to use front fogs only when appropriate.

The regulations for the wiring of the front fogs became applied to the rear fogs as well.

kiwi · Post by **kiwi** » Thu Nov 04, 2010 9:49 am

reminds me of that legendry forum thread of how many internet users to change a lightbulb

Ray was talking about Rear Foglights on a BX ....yes???????

You might want to go and switch on your REAR foglights on your BX and see how they operate before throwing the differant country regulation at me.

Post by **mat_fenwick** » Thu Nov 04, 2010 10:49 am

Rather coincidentally I was changing a rear foglight bulb yesterday, and yes, I can confirm (on my BX) the rear foglights are only illuminated when dipped beam is on. (Would you like me to post up a video of this?

)
We can only speak from our own experiences, all I think electrokid was trying to do was point out that your observations may not be applicable to those in the UK if there are wiring differences on cars for different countries.

Post by **Defender110** » Thu Nov 04, 2010 2:21 pm

Only illuminated through the headlamp circuit i.e. both dipped and main beam but not side lights!

Brian · Post by **Brian** » Thu Nov 04, 2010 2:32 pm

Just checked my rear fog lights -

They work on both dipped and main beams only.

Linegeist · Post by **Linegeist** » Thu Nov 04, 2010 3:33 pm

I suspect that's the way it's supposed to be. It's the FRONT foglamps that are supposed to extinguish with dipped beam IIRC.

The rear foglamps should be independent as they can be used in conditions of poor visibility and when front fogs would be unsuitable - such as heavy rain or snow.