I have a 09 Ultra with 10,000 miles on it. I baby the bike most of the time except for last week I was riding it more agressive and the check engine light came on and it went into lymp home mode. I checked for codes and it came up with P1511. The manual says it is the Throttle Grip Sensor. I replaced it and cleared the code. Same thing happened again after around 100 miles. Any ideas where to go from here ?