The reason you don’t hear the PWS when driving forward is because Tesla uses the minimum EU in it’s directive for AVAS at 56dB
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What are the sound levels for AVAS?
At speeds of 20 km/h, the minimum sound level for AVAS is 56 dB(A) [EU 2017/1576, Annex VIII, §III.3.a(i); UN 138.01, §6.2.8]. This...