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

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• 

 

[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!

 

[edwardbahaw]

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.