Where is speed sensor A located on 2006 Toyota Tacoma Prerunner?

Hello, "speed sensor A" is likely related to automatic transmission function. But, you can't just go throwing parts at a vehicle when you get a trouble code. You need to have testing performed in the related circuit for that code. Your guessing has wasted you tons of money already. Best to seek professional guidance from the start. Use this link to find some shops near you that can help with your concern: www.repairpal.com/repair-shops