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Discussion Starter · #1 ·
Is there a way, how to see during driving when exactly are hydraulic brakes active? E.g. by monitoring actual hydraulic pressures from braking ECU, using OBD plug and an app?
I’d like to know, when I am braking only by recuperation (no Energy waste) and when my braking is supported by friction between brake-pads and the brake-disc (creating heat Energy losses). Thx
 

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When the power gauge needle swings over to full charge (green /left side on analog dash), the car is using friction. I do not know how to see this via OBD. FYI there is always energy loss even when using regen - 2nd law of thermodynamics means you lose energy through heat generated in copper wiring, power electronics, motor, gearbox, tires, etc.
 

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Discussion Starter · #3 ·
When the power gauge needle swings over to full charge (green /left side on analog dash), the car is using friction.
I don’t think so. When I am braking in low speeds ( e.g. stopping at traffic lights from 30 to 0 km/h) I can hear sound from caliper friction , starting during very low speeds. In this moment power gauge needle is in green area, but close to 0 (almost vertical). Due to motor low rpm is only regen braking insuffitient and needs to be supported by friction too. This might be happening also in higher speeds during intensive braking.
 

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Not what you're looking for but the best way of avoiding the friction breaks is to throw it into B mode (or gradual d1, d2, d3) in advance of a stop light, I play a little game with myself trying to time it perfectly
 

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They're set up to always use the some pad action alongside regeneration when you use the brake pedal. This has two benefits:
  1. Predictable and consistent brake pedal feel (most of the time)
  2. Prevents corrosion and contamination build-up
If you want maximum energy recovery, follow the advice above and use B mode.

There may be a way to get live output on brake actuation, but it's not available on torque pro. Perhaps on another app
 

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I know it's not the question asked by the OP, but as @Patent says it is useful to have some friction braking to prevent rusting/glazed discs and pads.

When we had the 225xe the braking became rather poor due to surface corrosion/glaze, despite having fairly mahoosive front discs.

After half a dozen hard braking episodes from 70mph to almost stopped the braking performance was noticeably better for a couple of months.

The car was mostly driven by the missus on her urban commute in EV mode so I suspect friction braking would have been near zero compared to regen.
 

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Right. I was thinking about friction braking from high speeds. For low speeds, you are correct that the friction brakes engage at ~5 mph or less to bring the car to a full stop and the power needle is certainly not pegged at full charge. I have noticed it seems to be the rear brakes that bring the car to a stop at slow speeds.
 
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