I just replaced the speed sensor on my 03 TC. My speedo wasn't working & I was also getting the Ch Eng warning. Replacing the sensor fixed both. On my bike it's located under the drive belt above the front sprocket. The electric connection is behind the side cover, I got the other end that's bolted (Near the sprocket) off with a small 1/4 ratchet & socket (there ain't enough room for a 3/8 socket to fit between the bolt & the sensor) Good luck! Bugs.