Hi, I read your post.The simplest tool is an OTC tool similar to the simple Bartec tool, and has no real diagnostic capability at all. You can't do anything with it unless the car is in the "learn" mode, in which case it will excite the sensor and the only way you know it worked properly is if you get a honk of the horn indicating the sensor sent its info to the TPMS computer in the car.
Have a nice day...
