HELP! 86 300E would not start this am

[J.HIDALGO]

I did not have time to look at it since I was on my way to work. Current symptoms: all the cluster lights would light up, I could hear the fuel pump working but, the engine would not turn, nothing, limp, no noise, nada. I suspect the ignition module or the starter? I do not think it could be the OVP or the fuel pump relay (since I can hear the fuel pump energizing). The battery is 1.5 years old. Any suggestions?
P.S. It has been raining a LOT here lately. It did this once last week but, after the 3-4th try (turning the key) it started as usual.

[Mike Murrell]

J.

Doubt if I can input anything that hasn't already crossed your mind, but here goes anyway:

- Battery is young, but....set VOM on 20 scale and test for 12.6 volts. That of course is optimum. In my experience, once it gets below 12.0, cranking fades out. I realize that a LOAD test is better, but I believe this simple test says alot about the batteries general state of health.

- Battery cables secure and posts/connections clean?

- When you crank with headlights on, do they dim at all? I believe this might indicate if juice is actually making it to the starter.

- I recently went thru a very similar experience. Turned out to be a situation with the anti-theft circuit.

[Benzmac]

Engine would not turn? Put the shifter into Neutral. Then try. Also, see above.

Brother of The Benz, j.hialgo
Ofcourse rainy weather and battery post to cable corrosion is made worst.
You state it did this once before and it finally started after repeated tries. What occors is by trying again the resistance between the post and cable becomes hot and finally conductivity happens, whoa was that a long sentence. If that is your problem!
Starters don't normally expire without some previous warning, and I don't believe the Ignition Module will keep the starter from engaging and turning the engine over.
Doing all of this rambling keep bringing me back to the "Battery".
If you haven't already cleaned the posts and cables, do it and see what happens.
Make note that the groung cable attaches to the chassis close to the battery. I think that is connection X/40, or close to it. Clean it also.
Happy Trails Beep Beep from The Spiderman in Houston!!!

[J.HIDALGO]

Thanks for the advise, I will try it soonest. I had a terrible and long day yesterday. I will let you know what I found...

Nuetral Safety Switch

Brother of The Benz, j.hidalgo
Sorry about the reply, but I just had to try the humungus print size.
Happy Trails Beep Beep from The Spiderman in Houston!!!

[J.HIDALGO]

I tried starting the car with the shifter in neutral. It started right up! I guess I have to break out the manuals and repaired / replace it. Any tricks to it? Where is it?
Thanks again!

[Mike Murrell]

J. H.

Check out the following thread. Maybe it will help.

Neutral Switch

Brother of The Benz, jhildalgo
The Nuetral safety switch is mid way on the driver's side of the transmission and just above the oil pan flange.
After you have purchased the new switch all of your questions will be answered as to how it is removed.
We all think you owe your moderator a huge thanks.
Happy Trails Beep Beep from The Spiderman in Houston!!!

[J.HIDALGO]

Not only to Benzmac (who diagnosed the problem right away), Donald, Mike and every body in this forum. I finally got some free time and replaced the Neutral Safety Switch.
For the benefit of the whole forum I made some observations that may help somebody else with the same problem.
I looked through the archives and found step by step directions from downeyjc who replaced his switch in March 2001 (search: REPLACING NEUTRAL SAFETY SWITCH ON 126 CHASSIS). He has a 1985 300sd but the part number is the same 000 545 49 06. I suspect this part fits most "older" MB's. Check with your parts person/dealer. The only step that was not accurate was step # 4 (he was working from memory, I guess) in which you rotate the white ring clockwise to unlock, counterclockwise to lock the electrical connector.
I have access to a lift, which makes things a lot easier, since there is barely any room to work there. Follow those instructions and you shoul have no problem. The only minor problem I found was the new part did not align right away. TIP: connect the sift lever to the switch and THEN connect the two bolts in place. After that, it went right in.
I hope this can help somebody else.
Good luck!

Brother of The Benz, jhidalgo
You can see how when we all work together how everything works right.
It will be you who helps another Benz owner!
Wasn't it a blessing you had a Moderator with the knowledge to pin point the problem.
Thank You Benzmac.
Happy Trails Beep Beep from The Spiderman in Houston!!!