How common are electronic handbrake failures?

I'm thinking of buying a Volkswagen Tiguan, but I'm concerned about the electronic handbrake. I know someone who had a Tiguan roll down a hill after he had parked it. The dealer said that he must have forgotten to press the button to apply the parking brake but he swears that he did. Is there a record of this type of failure?

Asked on 20 March 2018 by Allen Lutz

Answered by Honest John
Generally, despite their faults, electromechanical parking brakes working on rear brake discs are a lot more reliable than lever type parking brakes because they clamp the brake discs more effectively. So I think this fellow must have forgotten to switch his on, and also failed to follow the Highway Code advice to always leave a vehicle in gear when parked on a slope.
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