I went out and bought one, and I have no clue how to use it? I want to check my tps sensor to see if it is any good, and have no clue where to put the ****? also I stick the red one in the middle wire on the tps, but where does that black go?

 

set the **** to 12v dc not ac. the red probe goes to the center wire and the black goes to ground, metal on vehicle or batt. ground. youll be checking for voltage not resistance (ohms). should show about .45 volts with the key on and throttle closed and 4.5 with the throttle wide open.