Hi the dealer wants to replace the timing belt because it has to be removed when replacing the sensor. There is also a balance shaft belt these belts break or loose teeth and destroy the sensor. You will not know untill you tear it apart. If not familar with this kind of job dont recccomend you can cause damage to your engine if the timing belt is not put back on correctly. Thanks mike here is the location it is not hard wired. Wire runs up acros valve cover.