The Trouble With Mr. Bean - S1-E8
Deliberate mistake: When Bean is putting on his socks as he is driving, his foot presses the horn in the centre of the steering wheel. Except that the horn control is actually on the right-hand column stalk (you can see the horn symbol on it). This was most likely an added comical sound effect.
Chosen answer: I'm guessing it is because he bought a new car. At the end of the first Bean, he crashed the mini. You hear the crash and see his wheel bouncing down the road. Safe to assume it was a write-off.
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