I have a 1990 300 SE Won't turnover. Everything else works. Car has been progresively harder to start in Park used to start in Neutral until yesterday. Couldn't jump it. NEw battery neede one any way did nothing to help. Is this the NSS or the Start Switch terminal. The ingintion switch seems to still function as it should. Hear a small click when it's engaged. please advise. I am out of work and can't take it anywhere.

first check all your connections start at the starter, it does sound like the NSS, if you were cranking it in neutral it could be out of adjustment also jump across your starter and see what it does, if it does nothing I would say starter and NSS, TRIAL AND ERROR check starter first it should turn over with it jumpered, if so replace NSS and adjust correctly. Jerry

Thank you just trying to verify the suspicions.

I will go lie in the snow and go from there. I'm pretty sure it's the NSS though. It has been funky for a while and jacking with the shifter has got it to start before. Just wish it was warmer -5 last night.

They get moisture in them and then they freeze..

A heat gun may get you on your way, but you need aNSS

Here is a trick that may work...

Hold the Key in the Start Position with left hand as you move the shifter lever past both sides of N.

You can also jumper he NSS at the V and V/wht wires by the gas pedal.

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A Dalton

On a similar topic where would be the NSS for a 87 190e ?
I crawl underneath driver side clipped on a wire dropped from top so I can route it back to battery positive, it starts now very well, Thank God.

I do want to find out where the NSS hides.
TIA

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The NSS is easy to get to on a W126....its on the drivers side of the trans, connected into the shifter arm on the trans. With the car on ramps you can get to it pretty easily. This is what one looks like:

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Similar to what was posted above... it's the flat thing with the cable going into it on the side of the transmission, left side IIRC.

On my '87 190D I replaced the NSS only to find that I had a broken wire in the harness right at the terminal going to the NSS. Switch was fine. The wires can easily get really corroded down there, I'd suggest examining them carefully before condemning the switch.

Get the shifter bushings and replace at the same time - it firms the shifter up to like new again.

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