2002 vw jetta door sensor locations?

I am having an issue with my drivers side door sensor. I have yet to do anything with it, but from what I know about VWs (i have owned and worked on them for 12 years) the door sensor is located in the door latch. I am currently looking into whether I can replace just the sensor or if i have to replace the whole latch...I read that the latch costs about 150.00. to install it, you would have to remove the door panel which can be tricky.