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Kona Electric Premium, Pulse Red, manufactured October 2021
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Discussion Starter · #1 ·
There are 4 different ways I can think of coming to a stop in traffic and remain stationary:
  1. (Auto hold OFF) - brake to a halt, and keep foot on the brake.

  2. (Auto hold OFF) - brake to a halt, and engage parking brake

  3. (Auto hold ON) - brake to a halt and rely on auto hold

  4. (Auto hold ON or OFF) - brake to a halt with the left paddle. The car behaves as if auto hold is ON.
I never use case 1.

Conventional wisdom, expressed in these forums on many previous occasions, seems to be that in case 3, auto hold works by engaging the parking brake, but in case 4 the car is held in position by the motor, thus (presumably) consuming power. (Hmmmm!) However:
  • When manually engaging the parking brake, or when engaging "Park", I can always hear the parking brake mechanism as it engages and disengages, but for case 3 I cannot - so can it really be that the parking brake is being engaged to implement auto hold?

  • When using auto hold, careful use of the right foot can make the car move away smoothly, with no jerk. When stopping using the left paddle, the car always jerks when moving off, which would seem to imply that it uses a different "hold" mechanism from that used by auto hold.
I therefore find myself wondering - entirely inconsequentially, of course, what mechanism(s) the car has for keeping itself stationery apart from the parking brake? And are the various differences I have noted indicative of multiple different mechanisms, or just indifferent software controlling the available mechanism(s) in inconsistent ways?

All of which is entirely unimportant - probably! :) - but does anyone have any definitive answers? Or am I alone in my observations?
 

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Conventional wisdom, expressed in these forums on many previous occasions, seems to be that in case 3, auto hold works by engaging the parking brake, but in case 4 the car is held in position by the motor, thus (presumably) consuming power.
No, not the parking brake. With auto-hold on it automatically applies the brakes, same as if you had your foot on the brake pedal. The brake lights even stay on which they wouldn't if it was the parking brake.

In case 4 it is held by the motor but only as much as it has to so it won't consume power if you're on a flat road. In fact on the flat it doesn't really hold the car at all and it can rock slightly and somewhat disconcertingly.
 

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Someone mentioned in another thread recently that when you come to a stop with the left paddle there is some kind of valve that is operated hydraulically. It keeps the pressure up in the drive train and therefore it isn't using electricity.
 
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