Battery's fine, instrument panel lights up, glow plugs work and then I turn the key and nothing happens.. I cleaned the battery posts so that't not the problem.

It there a way to hot start this thing like you could with the American cars??

Yes, the starter itself can be ' shorted' just like American cars...
but cleaning the posts may leave the other end of the cable still not transmitting electricity...AND on our old cars you can get enough corrosion under the rubber near the battery to make a difference... might just put new cables with cleaned attachment points on the car and then go from there...
Are you getting NO noise.. no clicking or anything ?
Do your inside lights dim when you put the key to ' start' ?
Open your door to turn on the inside lights...

Some 123's have a junction box on top of the right inner front fender. If yours does, jump terminals 1 and 3. This should energize the starter. If it still doesn't turn, check the voltage at the terminals. If there is voltage there, the problem is between there and the starter, probably the starter itself.

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1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13

Check the cube relays attached to the firewall just aft of the exhaust manifold side.

If not that check the neutral safety switch.

And if that doesn't work, jump the large bolt to the small bolt. I ruined a perfectly good metal file in a pinch but it worked!

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1974 240D 3.0L 4(M) - 250K -OM617.910 + 300D FW + Rajay turbo power!
1977 6.9 3(A) - 84k

I used a piece of coat hanger for about 2 weeks waiting on
a neutral safety switch to get in, In fact, I even bent it in a loop
and put it on a seperate key chain...........still in the console.

__________________
81 Mercedes 300SD 289k.......SOLD
82 Mercedes 300CD 252k......slow ride

82 mercedes 300 SD...mi Unknown
83 Mercedes 300D ????ksniff..gone too
84 Mercedes 300D 148k........SOLD
85 Mercedes 300TD 386k and holding some one elses project

this should be a 115 car
On my car my dad wired up a starter button under the dash before I got it. So the ignition switch went out I would think?

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1976 240D
1976 240D parts car
1970 220D daily driver

When you turn the key to engage the motor the light don't dim at all.

On the firewall there are these two boxes, with and without the covers.

Photo 1



Photo 2




On the driver-side inner fender there are these two boxes, covered and uncovered..



Photo 2



Photo 3, looks like a fuse is broken



Then there's this..



And these are the bolts on the starter itself..




Which is the right place?

I recall a relay under picture #1/2 which was the culprit in my case but I could be wrong, it was 2 years ago.

__________________
1974 240D 3.0L 4(M) - 250K -OM617.910 + 300D FW + Rajay turbo power!
1977 6.9 3(A) - 84k

Looking it over I should replace the cables and all the fuses too but for now I just want to get it started. So I hope from the photos I can get clear instructions how to do that.

Jumping the phillips head and the top hex nut on the starter should do it. What's that loose ground wire on the manifold bolt?

__________________
1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13

I have no idea what that ground wire is by the exhaust, maybe it was a part of the AC system?

But anyway I did the the bolt thing on the starter and it is running now so we know the starter is good. I think I'll get new cables for it and hopefully it's start properly after that.

Thanks for all the help.

What you did to start the car simply bypassed the ignition switch. Normally, the ignition switch would send power to the wire attached to the phillips head screw terminal on the starter, so you can safely assume that there is a problem somewhere between the ignition switch and the starter. Use a test light on that same screw to determine if any power is going to the terminal. Clip the alligator clip to the negative battery terminal and then hold the probe end of the test light on the screw. Have an assistant hold the key in the start position, if the test light does not light, you do not have any power from the ignition switch, if the light does come on, you probably have a partially broken wire in the circuit or high resistance in the switch. In this case you could show power at the terminal, but there would not be enough current flow to energize the starter solenoid. You might find the source of the problem in this case by having someone in the car hold the switch in the start position while you wiggle all the wiring you can find. If you wiggle something and the car cranks, you know you have isolated the problem. I am assuming of course that prior to this you have checked or replaced all the fuses in the starter circuit. I hope this helps you.