HELP! S-320 will not start! but finally got to start with direct power to starter

[Newinport]

Hi, I'm new to the site, before I start let me say this is one of the best site site if not "THE" best site online to get ingo on your Benz. I got this 95 S-320 about 3 months ago, car ran real good 105K original 1 owner, about 8 weeks ago I got off work, got inside the car but it would not start, I had the car towed to my house (good thing it was on a friday!) check all the fuses, tried moving/shacking the shifter while trying to start the car but nothing, but let me says all the lights in dash comes on when you turn the key to the start position. I tried the playing with the remote alarm and locking the door in every position posssible, but still nothing, NOT EVEN A CLICK, so I jump start the starter and the car started.. YES!! but now I have a toggle switch under the hood (and it looks bad when I go somewhere) to start the car.
I even got lucky enough and found someone who had the same model/year Benz who let me try ALL the relays under the hood on my car, But still NO START!! Any input would be help full. Also let me say thanks to the very helpful Benzworl member Phan, who guided me here, when I did not know how to post my question. Thanks buddy, and thanks to you all.

[NZ Benz]

Crank position sensor? I dunno wait for some of the tech gurus to post.

[MikeJT]

Hi Newinport,
I've had a couple of situations when the immobiliser has been activated unexpectedly but they may not be relevant to your case - I have a non-factory-fitted, RF-activated ATA and central locking system, rather than the usual IR system.

On one occasion the system seemed to get its knickers in a twist after I locked and unlocked the car in rapid succession. Same symptoms as yours. I pulled fuses 2, 3 and 15 in the auxiliary fuse box in the boot, left them out for around 10 secs to let the volts decay and then replaced them. Everything was then OK. This has happened once in 8 years.

The second situation arose while I was having to lock and unlock the car manually with the key because the PSE pump had failed. I found that the there was some interaction between locking the boot and activating the immobiliser. If I simply unlocked the driver's door and left the boot locked, then the immobiliser might be activated. I didn't pursue this in detail because the new PSE pump overcame all that.

Good luck, anyway.

Mike

[chuckindetroit]

There is a switch on the side of the transmission that controls the backup lights, gives shift lever position info to the computer, and will only let the car start if in park or neutral. Sometimes refered to as the neutral safety switch. A set of contacts there is in line with the starting circuit. These switches can be damaged by water/salt over time. I took mine apart and fixed it. They are about $40 at online suppliers. This could be the cause. Check out this thread for details http://www.benzworld.org/forums/w140...ar-switch.html

[Newinport]

I thank you guys for the help, I'm going to try to remove the fuses and see what I get, and if that does not work, then I'll replace the reverse switch by the transmission. Thanks again and I'll keep you guys posted.

[CSEMLAG]

I`ve got my car 3 months ago from original owner ,it is 1995 S320 and got 100000 miles.I have had the same problem 2 times already.Just waited few minutes and it started on his own.I had the same problem few times with my brand new VW Phaeton in past 3 years

[Newinport]

Hi all; I got a new neutral safety switch, intalled it and my car still will not start with the key, does anyone know how to adjust the neutral switch once it's installed? I tried moving it to different position while I had someone starting the car, but nothing. I had them hold the key to the start position while I was moving the neutral switch to different position but nothing.......! Since it was getting dark outside, I put the after market toggle switch inside the car, at least now I wont have to pop the hood open to start the car. Any sugestions from any one on how to adjust the neutral safety switch or what else I can check!!!!!

[Mercedes Mechanix]

Originally Posted by Newinport

Hi all; I got a new neutral safety switch, intalled it and my car still will not start with the key, does anyone know how to adjust the neutral switch once it's installed? I tried moving it to different position while I had someone starting the car, but nothing. I had them hold the key to the start position while I was moving the neutral switch to different position but nothing.......! Since it was getting dark outside, I put the after market toggle switch inside the car, at least now I wont have to pop the hood open to start the car. Any suggestions from anyone on how to adjust the neutral safety switch or what else I can check!!!!!

Service and Repair


See first picture......


Removing and Installing

1 Release locking device for starter lockout switch plug (8) by turning white plastic ring (arrow) upwards in direction of arrow.
2 Carefully press off plug using two screwdrivers at the cable output and the tab.
3 Unhook shift rod (9) after removing the retaining clip.


See second picture


4 Unscrew hexagon bolt (51) and pull off range selector lever (52).
Installation Note
Attach range selector lever in such a way that the driver (54) engages in the lever.



See third picture


5 Unscrew both bolts (55) and remove starter lockout switch (53).


See fourth picture


Installation Note
Move range selector lever to position "N". Insert splint or drill bit (4 mm dia.) through driver (54) into locating bore in shift housing, then tighten retaining bolts (55). Pull out locating pin (arrow).

After getting the switch set back up, let us know and then we will assist with diagnostics of your immobilizer circuit. Try starting by verifying the validity of Lockout Relay 38, then go from there. Circuit 50 is the normal course of action.

Would also start with a subscription to the infamous alldatadiy.com website. It will be the best $24.95 you have invested for you and your Benz. This website is a user version of our Mercedes WIS (Work Information System).

Good luck with your task, Robert and Dietrich

[Mercedes Mechanix]

One other item.... is your cigarette lighter inoperative?

If so, there is a good possibility, the fuse is open and this fuse also served as your starter activation power for your start circuit for the MY in question.

Dietrich