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I understand that Gen 2 Volts cause the brake lights to come on when the car is regenning in "L" drive mode. So if you push the gas and speed up or stay same, no lights, but if you take off gas and slow down, lights. Is that the correct way it works? Is there a way to stop the lights since Gen 1 doesn't do that. I wouldn't want to be constantly putting on brake lights if I am not actually using the brake.
 

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It is based on a government standard for deceleration rate. If you are slowing down at a high enough rate, the brake lights come on. The Gen 1 Volts did not slow down fast enough in "L" to need the brake lights. In the Gen 2, if you gently slow, by feathering the accelerator, even in "L", the brake lights will not turn on, only if you are slowing quickly.
 

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The brake lights come on above a set negative g-level (I believe -0.12g) or if the brake pedal is depressed. This safety feature is not adjustable.

ELR had a soft recall to tweak this logic.
 

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I come back to, why does it matter what the brake lights are doing? If you are worried about extra wear and tear on the bulbs, stop worrying about it. New bulbs are cheap and I have probably only replaced bulbs one in the lifetimes of each car I've owned after about q50k miles or so. Turning off the brake lights upon heavy regen will hardly save you much. Plus I'd much rather be safe from someone rear ending you and pay for new ltailight bulbs.
 

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I understand that Gen 2 Volts cause the brake lights to come on when the car is regenning in "L" drive mode. So if you push the gas and speed up or stay same, no lights, but if you take off gas and slow down, lights. Is that the correct way it works? Is there a way to stop the lights since Gen 1 doesn't do that. I wouldn't want to be constantly putting on brake lights if I am not actually using the brake.
I'm with you, but I don't see that happening :(
 

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It is based on a government standard for deceleration rate. If you are slowing down at a high enough rate, the brake lights come on. The Gen 1 Volts did not slow down fast enough in "L" to need the brake lights. In the Gen 2, if you gently slow, by feathering the accelerator, even in "L", the brake lights will not turn on, only if you are slowing quickly.
What govt standard is this exactly?
I can practically bring a manual trans car to a stop by downshifting, I've never had an issue in decades of driving.
 

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I appreciate this feature. Even though back in the day with a manual tranny people would frequently slow down by downshifting, drivers nowadays are not used to seeing that, and simply don't pay attention like they should. I don't think I would even use L if I knew the brake lights never came on. I'd be too nervous about the car behind me!
 

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The brake lights come on above a set negative g-level (I believe -0.12g) or if the brake pedal is depressed. This safety feature is not adjustable.

ELR had a soft recall to tweak this logic.
Government mandate is rate of deceleration, not g-force. You can ride in L going downhill at a steady speed and the brake lights won't come on, seeing as that's exactly what L was designed for (surprise!)
 

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They use g-force measurement to trigger the lights. And, yes, even going downhill the lights will come on as long as the trigger is hit.

G-force and rate-of-deceleration are roughly the same thing.
 

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I was actually curious to know when my brakes lights are on, too since Houston traffic is full of tailgaters. So, I installed a brake light indicator just like my old Cadillac Deville had.
 

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What a fantastic idea! Here I was trying to come up with ideas for some type of small mirror system, I never thought of putting a second light inline.

Any chance you'd write-up what you did?
 

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I appreciate this feature. Even though back in the day with a manual tranny people would frequently slow down by downshifting, drivers nowadays are not used to seeing that, and simply don't pay attention like they should. I don't think I would even use L if I knew the brake lights never came on. I'd be too nervous about the car behind me!
This. I was nearly rear-ended when I was at the back of slowly moving stop-n-go traffic. I was letting my old ICE creep to move forward so no brake lights. I notice car behind me was coming in too hot so I mash my brakes instinctively (hind sight, would've helped mitigate damage to the person in front of me at cost of me absorbing all the crash energy). Car approaching me from behind was clearly not paying attention since they too mashed their brakes to avoid colliding with me indicated by the pulses of tire screeches. They didn't, thankfully.

They also clearly thought it was my fault they nearly crashed and honked me. I politely rolled my window down and pointed at the other 3 lanes of traffic to my left that were also stopped due to traffic. That calmed them down some what. They still gave me stink eyes and were gripping their steering wheel a bit much for stop and go traffic (readjusting their grip, moving around the wheel). I think I made them more mad because they could see my laughing expression in my driver-side mirror (the one I was using to observe them from). They were definitely tailgating me if they could see my laughing expression.

Angry people look funny.
 

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Nice job! I've been tempted to do that, too. Could you post a description and photos of how you ran the wires and where you connected them? Is the LED bright enough to be distracting?

I was actually curious to know when my brakes lights are on, too since Houston traffic is full of tailgaters. So, I installed a brake light indicator just like my old Cadillac Deville had.
 

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The old GM cars used a little fiber optic cable from each lamp that was monitored. They usually had three on each front fender (parking, low and high beam) and two in the back that were positioned at the dual filament tail/brake light--one for each side. So before fancy electronics you could see at a glance which lights were actually working. I really liked them back in the days when an eight track stereo was "premium sound" in your 'Caddy.
 

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The old GM cars used a little fiber optic cable from each lamp that was monitored. They usually had three on each front fender (parking, low and high beam) and two in the back that were positioned at the dual filament tail/brake light--one for each side. So before fancy electronics you could see at a glance which lights were actually working. I really liked them back in the days when an eight track stereo was "premium sound" in your 'Caddy.
My dad had a 65 and a 69 caddy where you had 5 physical buttons that allowed you to change FM channels. To program it, you turned the tuning knob to the station you wanted, then yanked the button, then pressed it in. The beast barely fit into the carnage with inches to spare in front and behind. The 69 was a coupe, so to doors were ginormous. You pretty much had to park it all by itself and hope nobody parked next to you. It had a t0- cu inch engine where when you put it onto drive and let go of the brake it would take you up to 25 mph in idle. The fuel economy was so horrible that you could ctually see the fuel gauge move down while driving. This was at a time when caddies still had tail fins. The cars drove like boats and you could feel bumps in the road at all. You just floated over them
 

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The old GM cars used a little fiber optic cable from each lamp that was monitored. They usually had three on each front fender (parking, low and high beam) and two in the back that were positioned at the dual filament tail/brake light--one for each side. So before fancy electronics you could see at a glance which lights were actually working. I really liked them back in the days when an eight track stereo was "premium sound" in your 'Caddy.
Ingenious design! Wish more cars now a days had this feature. Our fiber optics today are much more flexible, leak less light, and are cheaper to boot! This solution requires no power, just the laws of physics. Now you just rely on the kindness of strangers to flash their lights at you when you have a headlamp out. Or a cop pull you over with a warning. Or you catch it yourself if you're a responsible adult.
 
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