In this session, Mike gives you pointers on diagnosing no neutral light, as well as testing a neutral light switch. A common reason for neutral indicator light failure is a loose or corroded connection at the neutral switch. This can be a very easy fix. Always look for this as you remove the wires from the switch. The neutral switch works by completing a circuit for the neutral indicator light. A detent in the transmission shift drum pushes up on the ball bearing in the switch. The ball bridges the switches internal contacts and allows for continuity between both posts on top of the switch.