What's the 2003 Infiniti G35 turbine revolution sensor location?

Since You're asking this, there's a good chance You've come across diagnostic code P1716 -- the turbine revolution sensor is a common point of failure. It's located on the input side of the automatic transmission, so it can be a bit difficult to get to for a novice. However, if You're more experienced, it's possible to replace. Most drivers will want to opt to have this done professionally. Essentially, failure happens when the transmission control module (TCM) fails to detect a signal from the sensor, resulting in an illuminated check engine light. Sadly, this isn't something that You can "fix" -- it'll necessitate a replacement. It's best to have it checked out at Your earliest convenience, though; letting it go for too long can lead to other transmission problems up to and including failure of the transmission itself.