Instead of guessing the correct value, measure the resistance between tabs 1 and 3.
- Even if there's dirt/corrosion on the surface of the resistive element or wiper arm, you should still get a fairly accurate reading this way.
If you can't get a good reading that way, one of the tab 1 or tab 3 connections to the resistive element may be broken or damaged.
- Start with the knob set to mid-range then crank the knob clockwise while checking resistance between 1 and 2.
- If it reads open/no continuity the whole time, tab 1 is broken/damaged and you need to set it to midrange again and crank it counter-clockwise while checking between 2 and 3.
Scott