Regeneration brake light

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Jeff

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I have switched my mg zs ev for the mg5 ev, happy with the mg5 but unlike the mgzs ev I don't think the brake lights come on with heavy regeneration had anyone else noticed this,is it normal or is there a fault.
 
I'm pretty sure by law that the brake lights must illuminate when you reach a certain level of retardation.
 
Jeff said:
I have changed my MGZS EV for the MG5, very happy with the change, however unlike the mgzs,under heavy regeneration the brake lights do not come on,has anyone else noticed this or is it a fault.
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The default regen setting on the MG5 is KERS 2, I think it has to be set to KERS 3 for the brake lights to come on.
 
Jomarkh said:
Same here get in car turn it on flick to 'E' and KERS 3
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Me too. Wish it would stay there! OK, KERS may not play ball at 3 until SOC drops to ~95% but it'd be nice if the car would remember what it has been told.

As an aside, there is one heck of a difference in braking feel, between a fully charged 5 doing what it wants and one where KERS 3 is active.
 
I would only ever use KERS 3 temporarily when slowing significantly; otherwise it's too easy to accidentally slow too much and waste energy. KERS 2 is good for winding B roads or stop/start traffic. KERS 1 is a good default for when you're generally trying to maintain the same speed, be that 30, 50 or 70mph.
 
Jeff said:
I have switched my mg zs ev for the mg5 ev, happy with the mg5 but unlike the mgzs ev I don't think the brake lights come on with heavy regeneration had anyone else noticed this,is it normal or is there a fault.
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I have the EV and the brake light does not come on in regenerative braking and was told it should not, I just look in the mirror and watch the near rear ends as no one knows it is slowing down without brakes or lights.
 
My EV stays in Kers 3 all the time and does so on stopping and starting the car, if you treat the go pedal as if it was a scalecetric hand control you can ease of the pedal and slow down either fast or gently.
 
Maylandmale said:
My EV stays in Kers 3 all the time and does so on stopping and starting the car, if you treat the go pedal as if it was a scalecetric hand control you can ease of the pedal and slow down either fast or gently.
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Do you mean somehow it defaults to KERS 3 on startup? How do you set this?
 
Maylandmale said:
My EV stays in Kers 3 all the time and does so on stopping and starting the car, if you treat the go pedal as if it was a scalecetric hand control you can ease of the pedal and slow down either fast or gently.
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Sorry Yeh it will as your driving. ZS and that does de-fault to kers 3 the five de-faults to kers 2 and this part of the forum is for MG5 not ZS
 
Hi. I bought my MG5 a week ago and joined this forum about 5mins ago!

This is the only issue I have with the car so far (otherwise I absolutely love the car!!). I'm pretty sure the level 3 KERS does NOT activate the brake light. You can test this easily enough at night by using a signpost that is directing traffic going the other way. Apply the brakes just after the signpost and you will see the reflective sign become illuminated by your brake lights in your rear view mirror. Now repeat this using KERS3 without pressing the brake pedal. When I tried this the sign was not illuminated under KERS3 retardation alone.

Personally I think this is a design fault and somewhat dangerous. Yes, you can keep an eye in the mirror all the time and try to anticipate your braking needs but you shouldn't have yo do this. What about an emergency situation, for example where you don't have time to adapt your driving? If I am correct in my assumptions that the KERS3 does not activate the brake light, then I think the issue needs pursuing with the manfacturers.
 
Adee said:
Hi. I bought my MG5 a week ago and joined this forum about 5mins ago!

This is the only issue I have with the car so far (otherwise I absolutely love the car!!). I'm pretty sure the level 3 KERS does NOT activate the brake light. You can test this easily enough at night by using a signpost that is directing traffic going the other way. Apply the brakes just after the signpost and you will see the reflective sign become illuminated by your brake lights in your rear view mirror. Now repeat this using KERS3 without pressing the brake pedal. When I tried this the sign was not illuminated under KERS3 retardation alone.

Personally I think this is a design fault and somewhat dangerous. Yes, you can keep an eye in the mirror all the time and try to anticipate your braking needs but you shouldn't have yo do this. What about an emergency situation, for example where you don't have time to adapt your driving? If I am correct in my assumptions that the KERS3 does not activate the brake light, then I think the issue needs pursuing with the manfacturers.
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I'm guessing that you are doing the test in a fairly built up area, and so not actually travelling that fast when taking your foot off for KERS3 to start SLOWING the car? If so, because of the slower initial speed the ability to regenerate is reduced (less kinetic energy in the system) and so it will not slow you fast enough for the brake light to need to come on.... Have you tried at 50mph+?
From the description of KERS equivalence to ICE engine braking, I believe KERS3 is supposed to give a similar braking 'feel' as if you put the ICE in to 3rd/4th (depending on 5/6 speed gearbox) and taking your foot off the throttle... at slower speeds the engine braking in the ICE would not be that great, however at higher (motorway) speeds doing so would give a VERY sharp braking force (and also not light up the brake lights).... So I guess that you should think of KERS as being 'engine braking' for an ICE car and so not expect the brake lights to come on unless under extreme slowing.
 
Tape a reflector to the led brake light strip, you will be able to see when the brake light comes on by looking in the rear view mirror.
 
I've tried mine from 70 mph on a motorway slip road and no brake lights come on using KERS 3
 
Probably not exceeding the rate of deceleration where lighting the brake lights is required. I believe it is not as strong as the ZS is. Not had any issues in the last 2 months with other drivers and our 5 or the Leaf for the last 5 years either for that matter
 
Lucky5 said:
Probably not exceeding the rate of deceleration where lighting the brake lights is required. I believe it is not as strong as the ZS is. Not had any issues in the last 2 months with other drivers and our 5 or the Leaf for the last 5 years either for that matter
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I'm not worried about it but i do see some worried faces in the rear view mirror 😂🤣😂
 
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