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Discussion Starter #1
So the Leaf has the 2 handbrakes, the one on the stick you use with your hand (P/Park mode), and the foot pedal one. Recently a couple of times I felt the car roll back or forward on occasion when parking on the driveway, and even after applying the foot pedal handbrake, I had to keep my foot on the brake pedal to get into the P mode without some serious rolling of the car.

Tonight I tested it out just before I left a charger. After starting the car I took P mode off and went into D mode. But I left the pedal handbrake on and gently pressed the accelerator and it started to move, although a bit more sticky. I then went into R mode with just the pedal handbrake on and applied the accelerator again and it started to reverse.

That's not good right? I just want to check that's not normal even for a dual handbrake elec. car?

I have always used both handbrakes to park anyway, but it seems that the foot handbrake is not reliable, especially on its own.

Could it just be the handbrake cable needs tightened? Or does it suggest a larger problem? Also am just coming up for 60,000 miles and end of warranty, now would perhaps be a goodtime for me to get this checked.
 

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'P' is a physical lock on the drive train which prevents the rotation the wheels. It is not part of the braking system , just a safety feature built into automatic gear boxes for long years, and now incorporated into the LEAF drive train. It is not designed to be engaged on the move.
The foot pedal that operates the parking brake work through a system of cables to move brake shoes into an old style drum bake built into the rear bake disc, to give the required separation from the foot brakes. The required efficiency for the foot brakes is 50% the required efficiency for the 'parking brake' is , as I recall only 16%. So being able to drive through it is quite normal. thought of as
Before the introduction of dual line brakes on cars the parking brake had to reach 25% efficiency as it was also thought of as an emergency brake, but no longer.

Routine maintenance of brakes is always worthwhile.
 

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Discussion Starter #3
If I think back to my dirty ICE driving days, if I put the handbrake on and applied the acceleration when in gear, it would just rev the engine is all, the car wouldn't move. So why in the same circumstance would an elec. car move? Should the handbrake have the same principal on an car, be it elec. or ICE that the car won't budge if the handbrake is properly on, no matter how much acceleration you give. I don't even need to apply much acceleration to the Leaf when the foot handbrake is on for it to move either.

I do feel confused, which is why I am questioning everything. I don't remember this happening before in the previous 50,000 miles done in the Leaf. And it just recently got serviced/MOT'd to and passed with no mention of handbrake issues.
 

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My 30 kwh will do the same as yours eg move with the footbrake on. As said above the footbrake is a mechanical application of braking force on the rear wheels, but like some cars I've owned it's not strong enough to lock the wheels, which may be a safty feature in itself, after all if you accidentially push the footbrake down whilst driving, eg thinking it's a clutch, you would not want the rear wheels locking up.
 

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I do feel confused, which is why I am questioning everything. I don't remember this happening before in the previous 50,000 miles done in the Leaf. And it just recently got serviced/MOT'd to and passed with no mention of handbrake issues.
The MOT requirement is 16% efficiency only, not the level that you require. The LEAF parking brake was designed around current rules, most/ many older ICE cars were designed using brake systems in being before the change in legal requirements, even though that change was made over 30 years ago.
There are many component parts that are identical with parts on cars from the 1970's . Car manufacturers will never design new if they can avoid it.
I once had a really good quality car from the 1950's with single line brakes. On the footbrake we could get over 90% efficiency. On the Handbrake (Emergency brake as it was designated in the handbook) the highest figure obtainable was 18%, with both rear wheels locked up. We put two bags of cement in the boot and passed the test!.
 
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