Hi, I have a 1986 190D 2.5 non turbo.
The car will not start this morning.

I took the battery to have it tested and it is fine.
I cleaned the ground for the battery.
All lights and interior electrical components are working fine.

This happened awhile back and it turned out to be my neutral safety switch. At that time earlier in the year, I was able to start the car by moving the shifter through the gears to find the sweet spot. I readjusted the neutral safety switch and all was good.

Now, no start condition even after moving through the gears so I don't think it is the neutral safety switch?

Any ideas where to start looking?

Always good to specify what you’re experiencing specifically. No crank? Or crank but no start? I assume you are in a no crank situation.

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Current fleet
2006 E320 CDI
1992 300D - 5speed manual swapped

former members
1984 300D "Blues Mobile"

1978 300CD "El Toro"

For no cranking nothing I read rules out the neutral safety switch or bad shifter bushings.

I prefer a voltmeter for this but it can be done with a test light. Someone turns the key into the cranking position and someone verifies that the small wire going to the Starter Solenoid is getting voltage.
If no voltage there you next go to the Neutral Safety Switch and see if when the Key is turned to the cranking position you are getting voltage to the Neutral safety switch.
If you are getting voltage to the NSS your NSS is no good. If you are not getting voltage there your ignition switch is likely having issues.

The above presumes your shifter bushings are good.

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84 300D, 82 Volvo 244Gl Diesel

Just because it worked for a while after adjustment does not mean it does not need to be replaced. Is it original? How many miles on it?

edited to show what I meant to say

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Jim

The car started tonight. Hmmm....

Earlier today I was getting nothing. No cranking, no sound, just dead.

The car has 168K on it.

Th shifter bushings are brand new.

I may try to clean the contacts to the starter tonight. And then try checking the voltage from ignition to NSS and solenoid.

Thanks.

Check the voltage 1st. No point in pulling the starter until you know that the solenoid is getting voltage.

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85SD 240K & stopped counting painted, putting bac together. 84SD 180,000. sold to a neighbor and member here but I forget his handle. The 84 is much improved from when I had it. 85TD beginning to repair to DD status. Lots of stuff to do.

Can you jump a 190 from the terminal box on the right fenderwell? I do this with my SD with two screwdrivers. Good way to see if the starter is getting juice.

Is the SD terminal block under the Battery Tray?

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84 300D, 82 Volvo 244Gl Diesel

Not exactly. It is under the hood and on the right wheel well. Very easy to access. But yes it is below the battery but not obstructed by the battery tray. It has a plastic cap with four or five wires screwed down. Just touch a couple of the screws together with two screwdrivers and the starter fires. Screw nearest the firewall and one of the others.

My Starter after having various no crank issued finally stopped cranking completely. It turned out the brushes were worn to nubs.

Jumper wiring the wire terminal block or going directly to the starter solenoid can indeed tell you if something in the Starter is the issue.

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84 300D, 82 Volvo 244Gl Diesel

Fixed.

I validated I was getting voltage to the neutral safety switch first.

It turned out that I had to re-align the neutral safety switch. I had to drop the trans a couple of inches as well as remove the three rubber hangers of the exhaust first.

The two bolts that hold the neutral safety switch to the left side of the transmission are challenging to get to. Even with dropping the trans I needed to use a 10mm swivel socket to get to them. A 1/4 rachet is just too big.

After putting the gear selector into neutral I aligned the two holes of the plastic arms of the NSS and held them in place with a small bolt before I tightened it up.

Naturally, the 35 year old plastic snap that holds the NSS electrical connector disintegrated so I used a zip tie to hold it into place. It is very secure.

All seems good for now.

I hope this helps someone.

Seems like what you have verified the need to have some plan to trouble shoot and follow it.
By verifying that the Neutral Safety Switch was getting Voltage you also verified that the Ignition Switch was sending the voltage to it.

There would have been voltage going in and if the NSS was working voltage going out of the NSS.

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84 300D, 82 Volvo 244Gl Diesel

Thanks for getting back to us with the answer. Will help folks in the future who experience a similar problem.