Rear Fog Wiring

[Guest Noddy006]

Hi all, Can someone advise the right way to wire the rear fog so that it will operate when the car is either on dip or full beam as now required by the IVA. At present I have controlled a relay from the dipped wire from the light switch then to the fog switch. Is it ok to take a feed from the full beam to another relay and then to the same terminal on the fog switch. All help appreciated.

 

Thanks

 

Ian H

[TonySuperSpec]

Hi all, Can someone advise the right way to wire the rear fog so that it will operate when the car is either on dip or full beam as now required by the IVA. At present I have controlled a relay from the dipped wire from the light switch then to the fog switch. Is it ok to take a feed from the full beam to another relay and then to the same terminal on the fog switch. All help appreciated.

 

Thanks

 

Ian H

 

You can use two diodes as an OR

 

Join the diodes together at the marked end,

Feed diped feed to one

Feed main feed to other

 

THen use the joined point as the +ve for the fog switching.

 

B)

[Guest TerryBarry]

I'm puzzled - not difficult I know

I thought that the reasoning for only linking rear fogs to dipped beam - was would anyone use mainbeam in foggy conditions - I wouldn't.

Still without going through the regs with a fine toothcomb I don't know

Maybe I'll check my tintop tomorrow.

[Guest Eric]

 

this has me puzzled too

 

my rear fog operates when dipped headlights on

my main beam can't be on without my dipped headlights

no problem

 

does anyone have a copy of the exact wording of the iva requirement

 

cheers

ek

[Guest craig030774]

fed mine through side lights

[Grim]

my main beam can't be on without my dipped headlights

 

When main beam is on, dipped should be off, otherwise the filaments will overheat and you'll get a very short life of teh bulb, and probably illegal too.

[Guest robinj66]

 

this has me puzzled too

 

my rear fog operates when dipped headlights on

my main beam can't be on without my dipped headlights

no problem

 

does anyone have a copy of the exact wording of the iva requirement

 

cheers

ek

 

 

This thread might help IVA _ Fog Lights

[Guest boggybogstar]

So has anyone sussed an easy way to wire this yet?, I've helped a fellow builder with his wiring and have set it upso the fog light comes on with the sidelights (which is wrong - and is clear in the other post)

 

I can only see a solution by using two more relays on the dip & main feeds or using two diodes but both these methods seem ridiculous to me - are we sure there isnt a simple switched earth from the stalks that's only switched on dip&main?

 

cant we just take an earth feed of pin 56?, ie only activated when the right hand light switch arm is fully up?

 

[Guest Eric]

When main beam is on, dipped should be off, otherwise the filaments will overheat and you'll get a very short life of teh bulb, and probably illegal too.

 

DOH!

 

sorry, was having a blonde moment!

 

cheers

ek

 

struggling to remember how mine are wired, main on=dipped off

[Guest petelee]

Hi Guys

 

I had this very same problem at the beginning of June. It was solved with the help of tips from Longboarder and miikae, and I can tell you that their solution worked. It involves 2 diodes to the fog lamp, 1 from the main circuit, and one from the dip circuit.

 

Follow my topic from June 2nd and you will have your answer, complete with working diagrams too!

 

Pete