I have a 10 year old Toyota Sequoia that our 16 year old son will be driving for about a year before trading it in for something a little newer for him. The Yaw Rate sensor is malfunctioning and the Toyota dealership wants $1360 to fix it. How much safer does a 10 year old Yaw Rate sensor make this car? Do you think it is worth fixing?
There are basically two forms of Yaw rate sensors: Piezoelectric type and micromechanical type.
In the piezoelectric type, the sensor is a "tuning fork"-shaped structure with four piezo elements (two on top and two below). During straight ahead driving, the upper ones produce no voltage as no Coriolis force acts. But in cornering, the rotational movement causes the upper part of the tuning fork to leave the oscillatory plane creating an alternating current voltage which is proportional to the yaw rate and oscillatory speed. The output signal's sign depends on the direction (left or right).
In my opinion, a yaw rate sensor is not going to cause the vehicle to be any less reliable. If it is not effecting the drivability then I would not replace it.
Apparently this is a sensor that detects the stability of the vehicle. Take a look at this article, just the first page, that describes what it does.
Maybe they should try clearing the code first and see if it comes back. It seems like an uncommon sensor to replace...I would find out how they came to the conclusion that it needed to be replaced or take it to another dealer to see what they say.
From the article it looks like it could have been set off if the vehicle had a side slide and resetting it may take care of the problem. Sorry I couldn't be of more help.
〉 Answered on May 28th, 2010 by Lori Johnson, Owner and Instructor at Ladies Start Your Engines