The NSS will allow the starter motor to operate only when the vehicle is in either the Park or Neutral position. In any other position it will not allow power to go to the starter motor. If you have a vehicle with a manual transmission, you will have a Clutch Start Switch (CSS) instead of a NSS. The CSS will only allow power to travel to the starter motor when the clutch is fully depressed.

Using your wiring diagram as a reference, check for power into the NSS or CSS (1) and out (2) with the key in the START position. If there is power in, but not out, the NSS or CSS is bad. Figure 3.

If there is no power in, you have an open circuit in the wiring between the ignition switch and the NSS or CSS. If you have power out, but not at the starter "S" terminal, you have an open circuit in the wiring between the NSS or CSS and the starter motor.

Okay, so we now know how to diagnose two of the possible reasons for a "No Crank" condition. Next time we will discuss the third most common cause of a "No Crank" condition: The Battery. I will tell you how to properly test and maintain your battery. I will also dispell some of the more popular battery myths.