Parking/emergency brake
- Thread starter DrVlad
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Shifting to park is the only way that I know of.
If you are stopped (without Creep or Roll engaged), the "Hold" indicator will conveys you are in an electronic brake mode requiring you to depress the accelerator peddle to move. If you do not move, the car will automatically "shift" to Park after a few minutes of inaction.
Yes, open the door and get out of the car. It will engage the parking brake for you.
On an EV, there's no difference between P and applying a parking brake. With an automatic transmission, P locks the transmission, and locks the steering column on modern cars. The parking brake pedal or lever locks a friction brake. With an EV, there's a fixed gear non-locking transmission that doesn't shift. So without applying the friction parking brake, the car would be in neutral. So P applies the brake, and applying it any other way would put it in park.
Theoretically, a person might want to engage the parking brake without taking the car out of gear, but that's what the Hold function does. On an automatic transmission car, it would also allow you keep the car still without locking the steering column. Again, that's not an issue with a Lucid. So adding a manual way to engage the parking brake without the car being in Park would be meaningless. It would be in park.
DrVlad
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Thank you! I appreciate the detailed reply. So, if I understand correctly, shifting to P in an EV is just like shifting to N and applying the parking brake on an ICE vehicle. Correct?
Nope. Shifting to P is like shifting to P in an ICE car, not Neutral with the manual emergency brake pressed. There is no emergency brake in the EV, since the entire "drive train" in the EV is locked electronically.
In an ICE vehicle, the emergency brake is a mechanical pulling of the brake calipers. If the emergency brake cable breaks, your car moves. In an EV, there is no mechanical braking cable. If in Park, the car will not move until you shift out of Park.
Unmutual
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I don't believe this is correct. The manual suggests there is a "parking brake" that engages in certain circumstances, including when the car is put into park. From the manual:
The parking brake operates on the rear wheels only, and is independently controlled of the pedal-operated brake system.
The parking brake automatically applies when P (Park) is selected, and releases when any other gear is selected. It is also engaged by certain systems when a time limit is reached.See Vehicle Hold on page 80.
The red parking brake indicator is displayed on the Cockpit Panel when the parking brake is engaged.A flashing indicator signals either operating with a fault, or a parking brake stuck in operation.
If the indicator is amber, a fault has been detected and the parking brake may not be applied when the vehicle is in P (Park). This will be accompanied by a notification on the CockpitPanel. Contact a Lucid Service Center to have the fault repaired.
Emergency use
CAUTION: Driving the vehicle with the parking brake applied, or repeated use of the parking brake to slow the vehicle, may cause serious damage to the brake system.
In an emergency, pressing and holding the P(Park) button decelerates the vehicle to a low speed using the service brakes, then applies the parking brake.
That's true but I believe that he is right about there not being a cable. It likely uses a small motor on each caliper to "screw" things closed electronically by turning a gear to get the pads to clamp down. There's no cable that can break. If there's a fail in operation, since the calipers on each side are not connected by a cable, it's likely that one will work at least well enough to hold things until you can get it fixed. If the electrical system fails, you wouldn't be able to get it out of park, but it would be a moot point.
I would expect a relatively low chance of failure. Failures due to leaving the brake on by mistake won't happen.
Essentially, yes. There's no way to lock the drive shaft electronically, short of using the power of the motor to overcome any rolling in any direction. If you parked on a hill, it would be the equivalent of holding your foot on the accelerator enough to keep the car from rolling. It makes no sense to do it electronically when there's a mechanical solution, and the obvious solution is that there are calipers for that purpose. With an automatic transmission, there's a parking pawl, so it's also mechanical. The parking brakes reinforce it with more mechanical means. There wouldn't have been much point in trying to emulate the parking pawl by having something to physically lock the drive shaft when locking the calipers on the wheels does the job.
Great clarifications. I stand partially corrected!
However, you can drive an ICE car with the emergency brake applied, albeit with a lot of resistance and eventual smell from burning the brake pads. You cannot drive an EV when in Park.
But, then again, I am open for correction!
However, you can drive an ICE car with the emergency brake applied, albeit with a lot of resistance and eventual smell from burning the brake pads. You cannot drive an EV when in Park.
But, then again, I am open for correction!
