PCS

Put a leveling kit (3") on my 2019 Tacoma and PCS maintenance warning is on. Can I relocate the sensor in the grill or angle it down to reset the warning? Total lift with tires was 4 1/2"

 

Not your only problem. Headlight focus (especially for LEDs) become an issue when starting from higher. The safety sensor in the windshield is also going to be less efficient.

But that is just what I have observed from reading in TW. You do not need to take my words as gospel. Good luck.

 

There is alot of stuff that should be reset/re-calibrated/adjusted when modifying the ride height of a modern vehicle (especially one with ADAS) but you may find that many people/dealers that do ADAS calibrations may refuse to do so on a modified vehicle due to liability because there's no official calibration procedure for a lifted vehicle and no way to determine if the system will operate properly.
Toyota's recommendation is to disable PCS and Radar Cruise on a modified vehicle.

Also a VSC Zero Point Calibration should be done once the vehicle is aligned to help prevent false activation.

 

A pro grill moves the sensor down, some people also add a washer or two to angle the sensor down.

I would try and disconnect the battery for a bit too.

Make sure to have an alignment with a zero point calibration done, but that generally is a separate system.