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IVA compliant fog light switch?
snowy2 - 12/7/13 at 02:43 PM



this is a circuit diagram for turning an ordinary 4 pin relay into a latching relay to switch on the fog lights the momentary switch can get its supply from any convenient place under the dash.
once the side lights are on, if the momentary switch is pressed the relay activates and will "hold on " until the sides are switched off. the fog lights will then switch off and only come back on when the momentary switch is pressed again

[Edited on 13/7/13 by snowy2]


loggyboy - 12/7/13 at 03:07 PM

Im sure someone mentioned an alternative interpretation of this new rule, however, IMO, a system like this is the answer. However, with yours can you switch them off without turning the sides or engine off first? ie, if I just want to turn the fogs off but keep sides/engine on.

[Edited on 12-7-13 by loggyboy]


gremlin1234 - 12/7/13 at 03:11 PM

however, there is no way of turning the fog lights off without turning the side/head lights off.
- this would be a problem if something catches up with you.


adithorp - 12/7/13 at 03:13 PM

So your driving along the motorway atnight and run into a patch of fog and switch fogight on... Then you come out of the fog and switch them off, how? Switch off all your lights? :?


snowy2 - 12/7/13 at 03:22 PM

it is a simple matter of fitting a normally closed intermittent switch on the fuse side in series with the other switch. if the power is broken its all thats needed to switch off the lights.

it was based on this in the IVA manual.....

The IVA manual section 28 Rear Fog Lamps Note 4 1) states that: The rear fog lamp(s) may continue to operate until the
position lamps are switched off, and the rear fog lamp(s) must then remain off until deliberately switched on again.

there does not seem to be a requirement to separately switch off the lamps..


snowy2 - 12/7/13 at 03:26 PM

weirdly C+U regs do not specify a minimum bulb intensity for fog lights

C+U Fog lights

so 5W would seem to be fine......
odd things these rules.


gremlin1234 - 12/7/13 at 03:46 PM

quote:
Originally posted by snowy2
the momentary switch can get its supply from any convenient place under the dash.

for simplicity, it may as well pick up from the relay '30' terminal


loggyboy - 12/7/13 at 03:58 PM

quote:
Originally posted by snowy2
it is a simple matter of fitting a normally closed intermittent switch on the fuse side in series with the other switch. if the power is broken its all thats needed to switch off the lights.

it was based on this in the IVA manual.....

The IVA manual section 28 Rear Fog Lamps Note 4 1) states that: The rear fog lamp(s) may continue to operate until the
position lamps are switched off, and the rear fog lamp(s) must then remain off until deliberately switched on again.

there does not seem to be a requirement to separately switch off the lamps..



Rear fog lamps;
1.
They must be operational


I would argue that one of the operations of any light is that it can be switch on AND off by its designated switch. Just beacuse it doesnt specfically say so, doesnt mean you can assume whats correct, common sense must dicate.

As for the brightness, the E marked part of the regs will cover the brightness, which will be 21w.

[Edited on 12-7-13 by loggyboy]


Smoking Frog - 12/7/13 at 03:58 PM

Are you using a Sierra stalk? If so pin 56 is earthed when headlights (low and high beam) are on. Use this to earth a relay for the fog light. Haven't checked this with the new IVA regs though.
Stalk Pin Outs
Stalk Pin Outs


doobrychat - 12/7/13 at 10:01 PM

thats what I did... picked a feed from the from the headlight feed from the switch to power the mini relay via fuse to then illuminate the switch and power the fog light..

No probs with IVA..


snowy2 - 13/7/13 at 06:46 AM

i get the feeling that sometimes the IVA is a bit like MOT's its different in different area's of the country (its not supposed to be, but.....)


snowy2 - 13/7/13 at 06:49 AM

quote:
Originally posted by gremlin1234
quote:
Originally posted by snowy2
the momentary switch can get its supply from any convenient place under the dash.

for simplicity, it may as well pick up from the relay '30' terminal

yes....but i place my relays for lighting under the bonnet its a long run back for the switch to get its power from the relay so i tap into a live cct under the dash. if your relay is uder the dash it works well as a suitable switch supply.


loggyboy - 13/7/13 at 06:54 AM

quote:
Originally posted by doobrychat
thats what I did... picked a feed from the from the headlight feed from the switch to power the mini relay via fuse to then illuminate the switch and power the fog light..

No probs with IVA..


IVA changes though, the latest change makes the wiring more complicated. The other option is to wire a buzzer that triggers when the fog is on and the ignition is off.


rdodger - 14/7/13 at 09:37 AM

I had my IVA a couple of weeks ago and asked the tester about this.

The Fog light can come on as normal with dipped beam. No other action needs to be taken.

IF the fog light comes on with the side lights then it must switch off with the lights/ have a buzzer etc.

So really nothing has changed.

PS the fog light must be e or E marked also F or B marked. It lighting up brighter than the sun seems not to be proof of it being a fog light!

[Edited on 14/7/13 by rdodger]


loggyboy - 18/7/13 at 12:05 PM

quote:
Originally posted by rdodger
I had my IVA a couple of weeks ago and asked the tester about this.

The Fog light can come on as normal with dipped beam. No other action needs to be taken.

IF the fog light comes on with the side lights then it must switch off with the lights/ have a buzzer etc.

So really nothing has changed.



But the rear fog light should not come on with sidelights UNLESS the car has front fogs and they are switched on, as they can be switch on with sides only.


sprouts-car - 22/7/13 at 12:15 PM

quote:
Originally posted by snowy2


this is a circuit diagram for turning an ordinary 4 pin relay into a latching relay to switch on the fog lights the momentary switch can get its supply from any convenient place under the dash.
once the side lights are on, if the momentary switch is pressed the relay activates and will "hold on " until the sides are switched off. the fog lights will then switch off and only come back on when the momentary switch is pressed again

[Edited on 13/7/13 by snowy2]


In this diagram, the fog light will come on when you press the button, even without the sides on? Does that matter?


loggyboy - 22/7/13 at 01:31 PM

Oh yes, the numbers are a little confused.

This would work, but I still dont think it will comply with IVA as you cant switch the Fog off independently.

Fog Relay Option
Fog Relay Option


CARTEK - 7/8/13 at 09:32 PM

For anyone encountering problems with this new IVA regulation for rear fog lights then I'm please to announce that my company, CARTEK Automotive Electronics Ltd, have designed a tiny device that makes 'normal' fog light switches comply with this rule change. The Fog Light Switch Control Unit.
As now required by the IVA Manual, once our thumb sized device is installed then the rear fog light can only be switched on when either hi-beam or lo-beam are on then, if the head lights are switched off and then back on again then the rear fog light will not come back unless the driver specifically activates the rear fog light switch to do so.
With the head lights on the driver can switch the rear fog light on or off at anytime and this Fog Light Switch Control Unit has inputs from hibeam and low-beam so it also complies with the requirement to work in either state.
For further details contact Cartek:
02380 637600
sales@cartekmotorsport.com


snowy2 - 9/8/13 at 06:12 AM

on my wiring diagram above your right about it coming on if the fuse is on the live side of the switch......i forgot that my new current car has some issues that need resolving and one of them is it needs rewiring.....the original builder did some strange things so a fair few of my fuses seem to be between the switch and the device...weird i know.
a better place to get the supply would be from the -ve side of the switch. (or even the -ve side of the dip beam)
i am not sure which is the -ve side in every case on my car because when i look to fixing faults i often find scotched locked additional supplies to some switches......i really don't know what he was thinking of. i would rewire this one as well but dont have time just yet.


ste - 15/8/13 at 09:07 PM

quote:
Originally posted by CARTEK
For anyone encountering problems with this new IVA regulation for rear fog lights then I'm please to announce that my company, CARTEK Automotive Electronics Ltd, have designed a tiny device that makes 'normal' fog light switches comply with this rule change. The Fog Light Switch Control Unit.
As now required by the IVA Manual, once our thumb sized device is installed then the rear fog light can only be switched on when either hi-beam or lo-beam are on then, if the head lights are switched off and then back on again then the rear fog light will not come back unless the driver specifically activates the rear fog light switch to do so.
With the head lights on the driver can switch the rear fog light on or off at anytime and this Fog Light Switch Control Unit has inputs from hibeam and low-beam so it also complies with the requirement to work in either state.
For further details contact Cartek:
02380 637600
sales@cartekmotorsport.com


I can offer anyone on here free diagrams using off the shelf parts to do this for a few quid. u2u me if you want the diagrams. I'm in the middle of making a little tutorial video to put on youtube.


Sloan85 - 25/8/13 at 01:05 AM

Fitted the Cartek unit today. Very simple to do - just replaced the fog relay I had previously installed.



[Edited on 25/8/13 by Sloan85]


Acc8braman - 25/8/13 at 06:27 AM

quote:
Originally posted by Sloan85
Fitted the Cartek unit today. Very simple to do - just replaced the fog relay I had previously installed.



[Edited on 25/8/13 by Sloan85]


Hi, was it easy to fit?