Testing neutral safety switch

[gtxdude]

How do you test switch in car? I have single pole switch, do you put it in park & then neutral and see if it has juice going to it? Then make sure in drive gears there is no juice, I want to test it before adding tranny fluid in case I have to switch it out.

 

[BillGrissom]

Disconnect it from the starter relay. Connect a multimeter lead to the NSS wire and the other lead to the case of the tranny. Should measure <10 ohm in P or N. Then, measure to BATT-. Should be about the same. If not, you have a bad "block ground". It is below the tranny fluid level so you can remove it w/o worry.

If tests above fail, remove it and test it alone, pushing the plunger in with your finger (and moving other lead to NSS body). If that works, the rooster comb in the tranny is likely the problem.

 

[fishy68]

There's no "juice" going to it. In park and neutral it provides the ground for the negative pole of the starter relay. Test it like Bill said

BTW: if you ever have to swap out a NSS just jack the car up from the drivers side only. The fluid will run to the passenger side when you do that. A small amount may come out but that's it.