I thought I read that someone made a mod that indicated when regen braking was on and when the mechanical brakes became engaged -- anyone know of who makes it, threads about it here, links and etc? Thanks for info, Al
Al, You have a good memory. It was 2004 - 2005Â Prius who made the item. But, AFAIK, he never sold it. He made one for himself and posted pictures saying he was going to sell them, but I don't think that every happened. You could try emailing them to see if they'd make one for you.
It was partially because of that vapor-product that I built my own. The coastal one likely works similarly, given what few hints Dave has dropped about his prototype. . _H*
The easiest way would be to put a pressure switch on the hydraulic brake line for the front tires. It would turn on a light or sound a buzzer. Id prefer the buzzer at first so I could keep my eyes on the road and train myself as to when the mechanical brake is actually engaging. A super loud vibrating buzzer in your seat that feels like being electrocuted for wasting energy, lol
"The easiest way would be to put a pressure switch on the hydraulic brake line..." This makes sense but I'm not an engineer and would be afraid that the "pressure switch" might cause a varying of the pressure in the system and affect the braking. I actually am an engineer but not that kind. What to do?
The scangauge gets its data by repeatedly asking questions on the car's diagnostic bus, and getting answers back. You can have it ask questions about the brake fluid pressures, or the total braking torque being requested by the computer at any time, but you won't have an instantaneous display; it will be lagged by the delay between the repeated questions and answers. When hobbit built his LED brake-pressure monitor, I think it was because he really wanted to be able to see what was happening as it was happening.
The pressure switch would barely change the volume and won't cause a problem with the actual movement of the piston or directly cause uneven braking. I loosened the bleeder valve and let out quite a bit of fluid while someone was holding the pedal and the computer got upset even though the key was off. After that the computer refuses to send brake fluid pressure to that particular wheel because it sensed the large leak that I caused. after a test drive it still wouldn't work. I had to reset the brake computer to restore fluid pressure to that wheel. I certainly wouldn't want this happening because of my added pressure switch. I think it'll be okay because there are bigger natural variances in the mechanical hydraulic braking components I propose I test it out myself and report back.
The beauty of hobbit's mod was he just tapped off the voltage from the pressure transducers that are already built in—and those are analog transducers, not just switches, so the brightness of his LEDs would tell you something about how much pressure was being applied.
