Recently i was left for dead when my 1993 w124 300d om602 engine didnt want to startup. Ended up having to push it 5 miles in the middle of the night. Took it to a mechanic the next morning and he first thought it was the ingnition than he thought it was the neutral safety switch and ended up just installing a button under my dash to start it up. At first it was starting up just fine with the key but lately the only way to start it up is through the button. The problem with this is i give up anything electrically powered from turn signal to my dear radio. Any ideas on what this could be? How I can fix it? What its going to cost me?

You turn the key to glow, press a button to start the engine then you dont have electricity in the car? Sounds like at least a bad key switch.

Sixto
87 300D

I have a '93 300D and have had it not engage the starter with the ignition switch. At the same time the turn signals didn't work. Mine was as simple as opening the hood and the fuse box. Then rotating the fuses until the engine would turn over.

Sorry I can't tell you exactly which fuse it was. I wasn't being very analytical at the time. It was raining and the shotgun fuse wiggle got me on my way.

In my case the fuse lost contact while driving. After having the turn signals fail to work, I tried shutting off the car to see if they would work after restarting. Turned out to be a bad idea when the engine wouldn't turn over. If I had known that was a possibility, I would have looked for a roof or bridge to stop under before shutting off the engine and getting soaked.

So it could be as simple as a bad fuse or poor contact in the fuse box. Some fuses crack and still look good. Heck the cracked fuses can have intermittent contact.

Bad key switch?

My mechanic recommended checking the fuses, will do

if you can remove the under panel of the dash - you will see a wiring harness near the accelerator pedal snake up to about where the knee panel is - its a square 4 pin wiring plug, its 4 wires are

1 pair = starter bridge on P and N position
1 pair = reverse lamp bridge.

If you can short the 2 wires of the starter bridge you have then bypassed the NSS on the transmission. Check for 12V positive (use a headlamp bulb to test, it should light up fully bright if the circuit is clean) when you turn the key to start.

Voltage at this point but no starter activity can be 2 things

1 bad starter
2 security device intercept (if factory security module equipped) - its intercept relay is behind the gauges.

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2012 BMW X5 (Beef + Granite suspension model)

1995 E300D - The original humming machine (consumed by Flood 2017)
2000 E320 - The evolution (consumed by flood 2017)

Sounds like fuse #5.

IIRC, when the convenience module (long box inside the relay section, behind fuses) has bad solder joints, it can cause fuse #5 to blow. You may hear that box or possibly one of the other relays there buzzing before this happens. The next time (or a few later) after you hear buzzing, you may experience a no-start scenario.

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'85 300TD "Puff The Magic Wagon" - Rolling Resto
'19 Mazda CX-9 Signature - Wife's sled
'21 Morgan 3-Wheeler P101 Edition
'95 E300d - SOLD
'84 300TD "Brown Betty" - Miss this one
'81 240D "China Baby" - Farm grocery getter

Thanks for the help peeps, ill give it a try and get back to all of you asap.

It's not an ignition switch because it doesn't switch the ignition system. It's a switch activated by twisting the key.

Sixto
87 300D