Help! Fog Light Only Works With Dipped Beam.

[Pete Mar]

Gents

 

I have a bit of a problem, my rear g

Fog only works with the dipped beam, I know it shouldn't work with side lights but it should with the main beam.

 

I have my two relays which are both working fine and are eath switched. My problem is that the wire feeding the live to the foglight is taken off the dipped beam relay and If I put a wire to the main beam relay it will link and feed power to both the main and dipped beam at the same time and both elements will be on at the same time.

 

Any suggestion you be very helpful.

 

Cheers

Pete

[Grim]

I think that is how mine is wired. I always assumed if it was clear enough to use main beam, it's not foggy enough to need the fog light. Main beam in fog is instant blindness! I don't know about IVA requirements, they may be different.

[Guest Ian & Carole]

I think that is how mine is wired. I always assumed if it was clear enough to use main beam, it's not foggy enough to need the fog light. Main beam in fog is instant blindness! I don't know about IVA requirements, they may be different.

 

IVA requirement is on both dipped and main beam, stupid as you say but that what they want.

There have been loads of post with the answer to this.

 

Have a read here might help there are loads more in the "search"

 

http://www.rhocar.org/index.php?showtopic=35611&hl=%2Brear+%2Bfog+%2Blight

[Pete Mar]

Thanks for that.

 

Looks like I'm off to Maplins for a couple of diodes and providing a live feed from the main beam relay to the foglight switch. Nice easy fix and cheap as chips.

 

This really is a great site.

 

Cheers

Pete

[knights_templar]

its a way around the problem, but if they were wired live switch it would have been easier.

 

psssssttttttttt, read the manual, OR not AND.

 

but I would check the tester reads it the same way

[Pete Mar]

I know unfortunately the switches I have are from a late model Sierra so all the switching is neutral, I had to run a switched live to the relays and then switch the neutrals.

 

I'll run a testers over everything before firing it up for real.

 

Thanks

 

Pete

[knights_templar]

it is only the headlight circuits that are switched earth on the late switch

 

a switch is a switch just use it to switch live on all circuits

[Pete Mar]

Ok so the job is done and all is working as it should. The two diodes work like very well but just to be on the safe side I used the two out puts from the dipped and main beams to trip a relay which carries the main load. Probably a bit over the top but it works like a dream. Thanks for the help.

 

Pete

[knights_templar]

at least you are safe from a tester who reads it differently.

[Guest JammyJim]

This is what I did after advice on here, passed IVA in May no problem, though I did notice a very slight flicker on fog light, when you switch main to dip or vice versa.

 

JJ

[fry61]

Nobody mentioned that the light switch feed (from right column sw.) to the head/dip switch ( left column sw.) is the place to pick up the feed to your fog relay;doesn't matter if it's live or earth -- just feed the other side of the relay with the other L/earth as necessary-- via your fog switch. Or as the fog is only 21 watt ( maybe 2 x 21w) a relay is only belt & braces.

[Guest snowy2]

so far as i am aware its dip OR main beam, a lot of production cars only switch fogs on with dip......

[knights_templar]

so far as i am aware its dip OR main beam, a lot of production cars only switch fogs on with dip......

 

my point exactly, but don't assume that if a production car has it a kit car is allowed to

[knights_templar]

Nobody mentioned that the light switch feed (from right column sw.) to the head/dip switch ( left column sw.) is the place to pick up the feed to your fog relay;doesn't matter if it's live or earth -- just feed the other side of the relay with the other L/earth as necessary-- via your fog switch. Or as the fog is only 21 watt ( maybe 2 x 21w) a relay is only belt & braces.

 

but if switched live you don't need a relay at all

[Guest snowy2]

Wierdly the C+U Regs state no minimum intensities for the fog light bulb so 5w would appear to be ok....

http://www.legislation.gov.uk/uksi/1989/1796/schedule/11/made

i cannot find any newer legislation on this subject so assume these are still current.