Hello. My wife's has a 2016 Toyota Highlander AWD with an automatic transmission.  She has approximately 108,000 miles on it

Earlier this week the brake light and ABS light light displayed on her dashboard. I ran the scan tool. The code C1416: Rear Speed Sensor LH Circuit.Output appeared. After I scanned the SUV, the dash lights went away.

I brought the car to a mechanic. The code did not trip for the mechanic. He said he couldn't figure out what was wrong with the SUV. A few days later the dash lights kicked in again and then went away.

My wife said she feels some type of pulsing or vibration when the dash lights go on and off.

I'd test the continuity of the wire, but the speed sensor is attached to the wiring.  I've heard that rust (I live in northern New England) can also throw off sensor from rust bouncing around the wheel hub/bearing.

Any thoughts of how I can narrow this down. Especially since the speed sensor with harness is $300.

Thank you. Much appreciated.