Electrical question

[NiceCupOfTea]

I want to use my high level brake light as a foglight whilst retaining brake light use.

Can I just connect both up to the same lamp with a common earth or is this likely to cause any weird problems?

Car is an MX-5 BTW.

[Steve_D]

That would be against the law.
Maximum height for a rear fog light is 1000mm.

Whilst you may be happy to break the law I for one would be well pissed if I had to drive behind you.

Steve

[NiceCupOfTea]

Steve_D said:

That would be against the law.
Maximum height for a rear fog light is 1000mm.

Whilst you may be happy to break the law I for one would be well pissed if I had to drive behind you.

Steve

Calm yourself! Rear highlevel brakelight on an MX5 is mounted in the bootlid. Entirely legal. Plenty of owners have had their cars pass the MOT like this.

[fatjon]

No, lots of annoying jerks have passed like this.

[Paul.B]

Don't be suprised if you get other drivers driving with their main beam on whilst behind you. Nothing gives people the hump more than a mis-used rear fog. One at that level would only compound it.

Practical point - if in really thick fog ie less than 100m visibility not some wispy mist. You would be safer if the driver behind could pick when you were braking. Your middle high level light is more likely to catch his attention if only showing when the brakes are applied.

Paul.B

[stevieturbo]

NiceCupOfTea said:

Steve_D said:

That would be against the law.
Maximum height for a rear fog light is 1000mm.

Whilst you may be happy to break the law I for one would be well pissed if I had to drive behind you.

Steve

Calm yourself! Rear highlevel brakelight on an MX5 is mounted in the bootlid. Entirely legal. Plenty of owners have had their cars pass the MOT like this.

Totally illegal. Brake lights and fogs MUST have a separation of at least 100mm.

You absolutely cannot use what is recognised as a brake light as a fog light

[NiceCupOfTea]

Okay, one point at a time:

Paul.B said:

Don't be suprised if you get other drivers driving with their main beam on whilst behind you. Nothing gives people the hump more than a mis-used rear fog. One at that level would only compound it.

I am well aware of the regs regarding usage of foglamps. Why do you assume that I will be "misusing" it?

Paul.B said:

Practical point - if in really thick fog ie less than 100m visibility not some wispy mist. You would be safer if the driver behind could pick when you were braking. Your middle high level light is more likely to catch his attention if only showing when the brakes are applied.

Good point - but of course I will have the normal brake lights which are just as obvious being the same wattage. Again, I am perfectly aware of when to use foglamps!

stevieturbo said:

Totally illegal. Brake lights and fogs MUST have a separation of at least 100mm.

You absolutely cannot use what is recognised as a brake light as a fog light

Stevieturbo, I would love to see those regs. Pretty much every car I can think of has the brakelight and foglight in the same light cluster ie, under 100mm! Edit - I have indeed found something here - I find it very odd though as my last 3 cars all have the foglights practically next to the brakelights so can't believe they would pass an MOT! Atill academic though, because... Even if this were the case, the high level brakelight would be in use as a foglight, and so plenty far enough away from the regular brakelights. Likewise, where is the regulation that says you mustn't use a brakelight as a foglight?

Fatjon, many thanks for your "input" I would hazard a guess that the height of a "high" level brakelight on an MX-5 is no higher than the foglights on very great number of standard saloons and 4x4s. Even so, it will be no brighter than when in use as a brakelight. If I use it in a foglamp, the conditions will be such that it is necessary. If it is too bright and annoying then you are too close.

Anyhow, I think I have worked out a way of doing it using diodes. Failing that I will swap the cables over and then back to the reversing light foglight afterwards.

Thanks for the help chaps.

Edited by NiceCupOfTea on Tuesday 24th August 13:38

Edited by NiceCupOfTea on Tuesday 24th August 13:47

[tristancliffe]

Just wire one of the reversing lights to by the fog light, and use a red bulb (and/or tint the lens too).

The brake light would be SO annoying as a fog light, even if conditions meant a fog light was needed (in 15 years of driving I've only driven in fog where a foglight was legal twice). As it's high, it would be much closer to the eye line of following drivers, and potentially visible through the windows to further following cars. And being a 21W lamp, it'll be dazzling.

Sounds like a bit of a chav mod to me.

And yes, I currently own a Mk1 MX-5 with high level brake light (import).

[Paul.B]

tristancliffe said:

Just wire one of the reversing lights to by the fog light, and use a red bulb (and/or tint the lens too).

The brake light would be SO annoying as a fog light, even if conditions meant a fog light was needed (in 15 years of driving I've only driven in fog where a foglight was legal twice). As it's high, it would be much closer to the eye line of following drivers, and potentially visible through the windows to further following cars. And being a 21W lamp, it'll be dazzling.

Sounds like a bit of a chav mod to me.

And yes, I currently own a Mk1 MX-5 with high level brake light (import).

It sounds like you have come across REAL fog about as often as I have! Twice for me in 25-years and 1.1million miles. I have probably come across mist that people think is bad fog and jump straight for the Fog Light switch about 100,000 times. Some even class rain as Fog!!!
You try picking out Brake lights from Fog lights on a busy wet motorway.

Paul.B

[Paul.B]

NiceCupOfTea said:

Okay, one point at a time:

Paul.B said:

Don't be suprised if you get other drivers driving with their main beam on whilst behind you. Nothing gives people the hump more than a mis-used rear fog. One at that level would only compound it.

I am well aware of the regs regarding usage of foglamps. Why do you assume that I will be "misusing" it?

Because you are bothering to modify it!

Paul.B said:

Practical point - if in really thick fog ie less than 100m visibility not some wispy mist. You would be safer if the driver behind could pick when you were braking. Your middle high level light is more likely to catch his attention if only showing when the brakes are applied.

Good point - but of course I will have the normal brake lights which are just as obvious being the same wattage. Again, I am perfectly aware of when to use foglamps!

No they are not. That is why High Levels are now standard fit. They shorten reaction times of following drivers. LED ones even more so.

stevieturbo said:

Totally illegal. Brake lights and fogs MUST have a separation of at least 100mm.

You absolutely cannot use what is recognised as a brake light as a fog light

Stevieturbo, I would love to see those regs. Pretty much every car I can think of has the brakelight and foglight in the same light cluster ie, under 100mm! Edit - I have indeed found something here - I find it very odd though as my last 3 cars all have the foglights practically next to the brakelights so can't believe they would pass an MOT! Atill academic though, because... Even if this were the case, the high level brakelight would be in use as a foglight, and so plenty far enough away from the regular brakelights. Likewise, where is the regulation that says you mustn't use a brakelight as a foglight?

Fatjon, many thanks for your "input" I would hazard a guess that the height of a "high" level brakelight on an MX-5 is no higher than the foglights on very great number of standard saloons and 4x4s. Even so, it will be no brighter than when in use as a brakelight. If I use it in a foglamp, the conditions will be such that it is necessary. If it is too bright and annoying then you are too close.

Anyhow, I think I have worked out a way of doing it using diodes. Failing that I will swap the cables over and then back to the reversing light foglight afterwards.

Thanks for the help chaps.

Edited by NiceCupOfTea on Tuesday 24th August 13:38

Edited by NiceCupOfTea on Tuesday 24th August 13:47

[stevieturbo]

Hopefully the police will get you before you annoy and blind any drivers anyway.

[NiceCupOfTea]

stevieturbo said:

Hopefully the police will get you before you annoy and blind any drivers anyway.

I hear they're setting up a nationwide "Operation Cuppa" as we speak I plan on getting around it by fitting 4 extra bumper mounted foglamps wired up to the brakelight switch.

[NiceCupOfTea]

tristancliffe said:

Just wire one of the reversing lights to by the fog light, and use a red bulb (and/or tint the lens too).

I've already done this and it was my preferred solution; however, my mechanic told me in no uncertain terms that it will not pass the MOT. He advised me to use the high level brakelight for the MOT.

tristancliffe said:

The brake light would be SO annoying as a fog light, even if conditions meant a fog light was needed (in 15 years of driving I've only driven in fog where a foglight was legal twice). As it's high, it would be much closer to the eye line of following drivers, and potentially visible through the windows to further following cars. And being a 21W lamp, it'll be dazzling.

As I said before this was not something that had particularly occurred to me - I'm not convinced it's a major issue anyway. As said, I can't recall actually having to use it on the car before and I've had it for 4 years. 21w is the same brightness as a brakelight and if you are close enough to be dazzled by that in fog then you're too close! The only situation I can see it being genuinely dazzling is in non foggy conditions when of course it wouldn't be on.

It's a moot point anyway as it is below a meter above the ground and therefore legal.

tristancliffe said:

Sounds like a bit of a chav mod to me.

*shrug* if you reckon. As far as I am concerned I just want an OEM look - ie, no crappy caravan foglight hanging off the back bumper. If that's chav, string me up.

tristancliffe said:

And yes, I currently own a Mk1 MX-5 with high level brake light (import).

So you'll know that lots of people of mx5nutz/mx5oc have used the brakelight for a foglight then.

[NiceCupOfTea]

Paul.B said:

NiceCupOfTea said:

Okay, one point at a time:

Paul.B said:

Don't be suprised if you get other drivers driving with their main beam on whilst behind you. Nothing gives people the hump more than a mis-used rear fog. One at that level would only compound it.

I am well aware of the regs regarding usage of foglamps. Why do you assume that I will be "misusing" it?

Because you are bothering to modify it!

Hardly modifying - it needs a foglamp to pass its MOT.

Paul.B said:

NiceCupofTea said:

Paul.B said:

Practical point - if in really thick fog ie less than 100m visibility not some wispy mist. You would be safer if the driver behind could pick when you were braking. Your middle high level light is more likely to catch his attention if only showing when the brakes are applied.

Good point - but of course I will have the normal brake lights which are just as obvious being the same wattage. Again, I am perfectly aware of when to use foglamps!

No they are not. That is why High Levels are now standard fit. They shorten reaction times of following drivers. LED ones even more so.

So it's just as well that the high level brake light will work as per normal the way I am considering wiring it up! It's a miracle that we're all here today with our parents recklessly driving around in cars without high level brakelights, and God forbid, old-style filament bulbs...

I was looking for a bit of advice on the wiring chaps, if you want to whinge about foglamp regulations I suggest you do it to VOSA.

[stevieturbo]

Your mechanic is wrong. Fog light adapted from reversing light will pass MOT as long as it meets the spacing requirements.
It will also pass SVA that some imports have to comply with.

[NiceCupOfTea]

stevieturbo said:

Your mechanic is wrong. Fog light adapted from reversing light will pass MOT as long as it meets the spacing requirements.
It will also pass SVA that some imports have to comply with.

Well he's been working on MX-5s since they were new - they certainly won't pass at the MOT station he uses. It looks pink unfortunately. I happen to think it's by far the neatest solution so I may look into getting an aerosol of red tint for the reversing light.

Here's how it looks at the moment:



Here's somebody else's:



Just hope it passes - other alternative it gaffer tape the old fog lamp back together and hang it by the wires...

[fatjon]

Paul.B said:

tristancliffe said:

Just wire one of the reversing lights to by the fog light, and use a red bulb (and/or tint the lens too).

The brake light would be SO annoying as a fog light, even if conditions meant a fog light was needed (in 15 years of driving I've only driven in fog where a foglight was legal twice). As it's high, it would be much closer to the eye line of following drivers, and potentially visible through the windows to further following cars. And being a 21W lamp, it'll be dazzling.

Sounds like a bit of a chav mod to me.

And yes, I currently own a Mk1 MX-5 with high level brake light (import).

It sounds like you have come across REAL fog about as often as I have! Twice for me in 25-years and 1.1million miles. I have probably come across mist that people think is bad fog and jump straight for the Fog Light switch about 100,000 times. Some even class rain as Fog!!!
You try picking out Brake lights from Fog lights on a busy wet motorway.

Paul.B

About the same numbers. Maybe twice in my entire driving life have I seen fog bad enough to merit fog lights but still I get stuck behind some arse that thinks they are needed in rain, mist, on a clear summers night and in nose to tail traffic where we're so close I can see what mileage his cars done from behind. Now someone asks for help in wiring up his high level brake lights as fog lights just to get them to the right level to really piss other drivers off....

[NiceCupOfTea]

fatjon said:

About the same numbers. Maybe twice in my entire driving life have I seen fog bad enough to merit fog lights but still I get stuck behind some arse that thinks they are needed in rain, mist, on a clear summers night and in nose to tail traffic where we're so close I can see what mileage his cars done from behind. Now someone asks for help in wiring up his high level brake lights as fog lights just to get them to the right level to really piss other drivers off....

Oh for crying out loud! Once again:

• it is a COMPLETELY LEGAL height
• I have stated several times that I know when to use foglamps. Why do you assume (wrongly) that I will have them on in rain, mist, clear summers night, traffic, etc.?

and finally:

• If you are being dazzled by my foglamp, it will be very foggy by definition, and YOU ARE TOO CLOSE!

Now, please, if you have nothing useful to contribute, kindly go and bother somebody else!

[Paul.B]

'CupOfTea - Fair enough I'll leave it alone.

Can I make a suggestion? Fit the low level swingy type for the MOT and then remove it until the next MOT. I understand your dislike for them and that you need one for the MOT. As we have discussed. What are the chances of you ever really needing to use it?

Paul.B

[Slinky]

FWIW, when I had my Eunos (with the swinging, broken fog light) I wired one of the reversing lights to serve as a fog light with an LED bulb.. My MOT man said that it would fail construction and use regs, but was sufficient to pass an MOT, in fact, he rather liked it..