When it rains my parking assist sensor acts up!?

do you use parking assist? have you tried cleaning the sensor?

 

when i had parking sensors on my 2016 Prius they weren't bothered by rain so much as snow/slush during winter storms. Do you have any particularly grungy sensors? Caked on mud? The dynamic cruise likes to lose the car in front if there's enough water to reflect all the radar away but not actually block it so it doesn't know to throw an error and instead tries to ram the car in front. But in bad weather I tend to turn off cruise control anyway.

 

Might be a calibration thing requiring a moderately expensive visit to a Toyota dealer. You didn't say if there were any bumps or bruises to the vehicle exterior which could change sensor orientation or cause other internal damage. Might require sensor replacement if a seal has been compromised. It's one of those systems that just works, and if it doesn't there isn't much else to do but contact Toyota service.

 

All depends on the fine print of said warranty. I hope so too because the fix could be $$$.

 

The 2022 OM has a statement that says that might happen. How heavy a downpour are you experiencing? A body shop that is familiar with Toyota Safety Sensors might be open to helping you out.