Question

on the techwrench, the \u\ button serves what function? change to the desired torque unit increase the torque value power on and off to activate the \peak\ torque mode

Explanation:

Based on common knowledge about tools like the Techwrench, the "U" button is typically used to change torque units. There is no information provided to suggest the other options are correct.

Answer:

Change to the desired torque unit