Break light wiring

[matt_0199]

Right so I've purchased a F1 style break light for my mk3, I've got it all ready but when coming to wiring the cables to the break light I'm unsure which wire I need to to connect it to. Any help would be appreciated. Here's what the installation picture shows.

https://imgur.com/06JbQPq

 

[mty12345]

Black to ground
Red to the power feed to your tail lights
Yellow i'm guessing it means to connect it to the wire going to the brake light bulbs, then the onboard chip will strobe it when your brake lights are on. I'm not 100% sure on that, but it's the only thing that makes any sense as to how it would work.

One word of caution though, is it road legal? If not then i can't imagine the police would take too kindly to it. Get an especially shitty one and the may try and say you're impersonating a police vehicle. Also if someone rear ends you and says they were distracted by it, every chance it could invalidate your insurance as an 'undeclared modification' etc

 

[Seriously?]

Apparently road legal in the UK as part of an emergency stop system ( as fitted to Beemers and Mercs amongst others ) and activation must be completely separate to the 'normal' brake light system:

• All the lamps of the emergency stop signal shall flash in phase at a frequency of 4.0 ± 1.0 Hz.
• However, if any of the lamps of the emergency stop signal to the rear of the vehicle use filament light sources the frequency shall be 4.0 +0.0/-1.0 Hz.
• The emergency stop signal shall operate independently of other lamps.
• The emergency stop signal shall be activated and deactivated automatically.
• The emergency stop signal shall be activated only when the vehicle speed is above 50 km/h and the braking system is providing the emergency braking logic signal defined in Regulations Nos. 13 and 13-H.
• The emergency stop signal shall be automatically deactivated if the emergency braking logic signal as defined in Regulations Nos. 13 and 13-H is no longer provided or if the hazard warning signal is activated.

 

[matt_0199]

One word of caution though, is it road legal? If not then i can't imagine the police would take too kindly to it. Get an especially shitty one and the may try and say you're impersonating a police vehicle. Also if someone rear ends you and says they were distracted by it, every chance it could invalidate your insurance as an 'undeclared modification' etc

I'm sure the normal breaking light function of it is legal but you can set it up to flash when breaking which is only usually done when you're breaking quite hard. I'm not using that feature and only using it as a solid red when breaking. Not sure if I can declare on insurance though that's something which I'll have to check. Thanks for the reply though will try connecting it up later !

 

[mty12345]

I'm sure the normal breaking light function of it is legal but you can set it up to flash when breaking which is only usually done when you're breaking quite hard. I'm not using that feature and only using it as a solid red when breaking. Not sure if I can declare on insurance though that's something which I'll have to check. Thanks for the reply though will try connecting it up later !

No worries. In that case it may be that you just have to put black to ground, red to your brake lights and leave the yellow unconnected, but as long as the black goes to ground and the others to power, then you're not going to harm anything.

 

[black_sheep]

You do realise that the standard brake lights strobe/apply hazard warning lights when you come to a stop under hard braking on the Mk3 Leon anyway.

Video below may help.