I supply workshop diagnostics to workshops throughout the UK and teach and train technicians.
if the height sensors were the cause of this issue and could cause this fault then this would be a massive error for a workshop to make.
when the problem occurred it was 2 weeks after an air strut had been replace and the sensors calibrated by another Lexus dealer.
it was very heavy rain and driving through a puddle there was a squeal and then the car started to bounce.
The conclusion from two garages, one a Lexus dealer is that the air isn’t getting to the rear suspension units.
no leak can be found. Rear solenoid valve sets have been replaced, compressor has been replaced
both height sensors going at the same time would be very unusual.