Switch added to accelerator pedal to activate rear lights.

[edwardbahaw]

Hello MGEV peeps

Just letting everyone know that I have added a switch to the accelerator pedal on my MG4 which activates the load space red lights within the tail lamps. The system is powered by fuse 45 in the passenger fuse box compartment via a relay. It's set up so that whenever I release the accelerator pedal, power is sent to the load space lamps on each side which are just below the brakes lamps within the tail light assembly.

I did this as I always noticed cars behind get very close to me whenever I release the accelerator pedal and regenerative braking kicks in. The roadways on my country are quite congested so I did this as a precaution to reduce the chances of getting rear ended.

I have been working in the automotive industry for many years doing vehicle restorations so I am quite capable of designing electrical systems as upgrades to vintage cars. Most importantly I had a copy of the MG4 electrical workshop manual which is a major asset in helping me to quickly figure out the wiring. The brackets on the accelerator pedal for the switch which I fabricated did not need any new holes for installation as it was designed to bolt on the existing fastener for the same pedal.

The brake lights still illuminate when I step on the brake pedal so essentially I have 2 sets of brake light that illuminate in stages.

Hope this is useful to some of you!

Ed

 

[MG Clive]

Hi Ed, so are the rear red lights on all the time unless you're accelerating?

 

[siteguru]

Sounds to me that you've effectively created rear Daytime Running Lights (DRLs).

 

[Everest]

Just letting everyone know that I have added a switch to the accelerator pedal on my MG4 which activates the load space red lights within the tail lamps.

But.. according to @siteguru (so it must be correct), the brake light comes on when regen exceeds -1.3m/s^2

Post in thread 'Brake lights'

Sep 19, 2024

Search this forum for retardation rate and you'll find previous posts of mine (one or more of which link to the laws/regulations requiring this). If the retardation rate (i.e. how quickly the car slows down) exceeds 1.3 m/s^2 then the brake lights must come on.

• siteguru

• 
• 

 

[salty]

Sounds very clever. But not actually sure what he's done? Unless I'm being particularly fik. (Which is quite possible).

 

[slmorgan42]

But.. according to @siteguru (so it must be correct), the brake light comes on when regen exceeds -1.3m/s^2

Post in thread 'Brake lights'

Sep 19, 2024

Search this forum for retardation rate and you'll find previous posts of mine (one or more of which link to the laws/regulations requiring this). If the retardation rate (i.e. how quickly the car slows down) exceeds 1.3 m/s^2 then the brake lights must come on.

• siteguru

• 
• 

This is my understanding too.

 

[BingBong]

Under -7% regan the normal brake light turn on

 

[siteguru]

Please see my post #3 ... I think this mod merely turns on the tail lights, not the brake lights. This comment here is the clue:

whenever I release the accelerator pedal, power is sent to the load space lamps on each side which are just below the brakes lamps within the tail light assembly.

<snip>

The brake lights still illuminate when I step on the brake pedal so essentially I have 2 sets of brake light that illuminate in stages.

 

[decrep]

Makes sense to me, for my ICE car, I often slow down when I'm timing the lights a lot sooner than cars behind me. This would let them know I'm slowing down.
However, with the MG4, unless you always select regen level 1 it will only duplicate the existing brake lights. I'm sure at the default level 3 regen, taking your foot off the accelerator will activate brake lights.

 

[edwardbahaw]

Hi Ed, so are the rear red lights on all the time unless you're accelerating?

Basically ... yes!

Sounds to me that you've effectively created rear Daytime Running Lights (DRLs).

I will do a video to show to you guys .... I wired the pedal switch to the load space lights which are located on the tail lamp and can be viewed from the rear and are conveniently red. The moment I release the accelerator these red lights come on and the driver behind gets a prompt that I am slowing down and they slow down as well.

Before I did this mod ... I would notice the cars behind would get considerably closer whenever I released the accelerator.

 

[decrep]

I will do a video to show to you guys .... I wired the pedal switch to the load space lights which are located on the tail lamp and can be viewed from the rear and are conveniently red. The moment I release the accelerator these red lights come on and the driver behind gets a prompt that I am slowing down and they slow down as well.

Before I did this mod ... I would notice the cars behind would get considerably closer whenever I released the accelerator.

So what regen level do you use????
Foot off the accelerator at default regen should turn the brake lights on.

 

[Tuareg]

Nice and illegal in probably any country.

 

[Jamesrr]

Nice and illegal in probably any country.

What our AI Overlords think of the topic WRT to Australia...

Q: - Can you modify the braking light behaviour of cars in Australia?

AI Overview

In Australia, modifying the braking light behavior of a vehicle is generally not permitted and can be illegal. While there are specific rules for brake lights, including the requirement to show a red light visible from 30 meters, there are no provisions for altering their behavior beyond the standard function of illuminating when the brakes are applied.

Why modifications are restricted:

• Safety Concerns:
  Altering brake light behavior can create confusion and potentially lead to accidents. Flashing or otherwise non-standard brake lights can be mistaken for emergency vehicle lights or misinterpreted by other drivers, increasing the risk of rear-end collisions.
  
  
• Legal Compliance:
  Australian vehicle standards, such as the Australian Design Rules (ADRs), specify the requirements for brake lights, and these rules do not allow for modifications that deviate from the standard functionality.
  
  
• Confusion with Emergency Vehicles:
  Allowing flashing or non-standard brake lights could cause confusion with emergency vehicles, which often utilize flashing red lights for signaling.
  

What is allowed:

• Standard Brake Light Functionality:
  Brake lights must illuminate when the brake pedal is depressed and the vehicle slows down, regardless of whether the headlights are on or off.
  
  
• Replacement Bulbs:
  Replacing a faulty brake light bulb with an equivalent one is permissible, as long as it maintains the standard red color and functionality.
  
  
• Street Rods:
  In the case of street rods, a blue lens of a limited size (not over 20mm in diameter) may be incorporated into the brake light, according to AustLII.
  

Consequences of illegal modifications:

• Fines and Penalties:
  Modifying brake lights in a way that violates vehicle standards can result in fines, demerit points, and other penalties.
  
  
• Vehicle Inspections:
  A modified vehicle may fail a roadworthy inspection, preventing it from being registered or driven on public roads.
  
  
• Safety Risks:
  Non-standard brake lights increase the risk of accidents, potentially leading to serious injuries or fatalities.

So... Not really clear if such a mod would fall foul of the ADRs. I'd be hesitant to do it myself.

 

[decrep]

Not exactly modifying the brake light though, it's causing an extra light to come on when accelerator pedal is lifted.
The normal brake light is untouched.

 

[Tuareg]

Just as illegal in most countries is to lightly press the brake pedal to illuminate the brake lights if you 'think' they are too close to the rear of your vehicle. I'm sure modifying the braking system without declaring it to your insurance company (who no doubt will refuse policy cover) will invalidate the policy and quite rightly so. Good luck with an unmarked police car behind you, who will pull you over, check your insurance and look for that modification. Not on the documents? Then they'll contact the insurance company who will then most probably cancel the policy and you'll have to declare being refused insurance on any new policy.

 

[Ian Key]

It would be legal in the UK as you are using the side lights as brake lights and they don't meet the required specification. Also at night they are already lit so it would make no difference.

 

[Everest]

When I read the title "Switch added to accelerator pedal to activate rear lights." I was thinking it was to do something when you accelerate hard, like emit a smoke screen or drop an oil slick behind you - guess I spent too much time watching Dick Dastardly and Mutley in the Wacky Races as a kid

 

[Archev]

When I read the title "Switch added to accelerator pedal to activate rear lights." I was thinking it was to do something when you accelerate hard, like emit a smoke screen or drop an oil slick behind you - guess I spent too much time watching Dick Dastardly and Mutley in the Wacky Races as a kid

My brain was half a line behind you trying to figure it out too. You ought to patent the oil and smoke ideas

 

[Everest]

I think Hanna-Barbera already hold the patent from 1968.

 

[OriginalBigAl]

I think that one of the reasons the ardent ICE divers and anti EV brigade hate is the fact that when following our brake lights can be flashing on/off when we are feathering the throttle and letting it run beyond the -7% limit. I know it annoys me ,and I know the reason for it. They could see this as bad driving, arrogant brake checking, stupidity. Add on that most of the time we are unaware its happening , or if we are, there is not much we can do without altering the cars configuration they might see us as an ignorant portion of the population without having the gumption to research and learn why this is going on for themselves.
Maybe its time for another 1970s government backed information / education film . "Engine braking versus re-gen braking. Learn the facts Wally! " Jeremy Clarkson seems to have been missing from our screens recently.