Author Topic: Car wont turn off  (Read 3187 times)

biffabeau

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Car wont turn off
« on: July 25, 2019, 10:08:30 »
Hi.  I've am getting my car back on the road again after a period off the rails myself.  Coming across a few hickups.

Engine is running ok until you go to turn her off. You can literally turn and remove the key and the engine continues to run.
Any ideas please?

Thank you

Paul & Dolly

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Re: Car wont turn off
« Reply #1 on: July 25, 2019, 10:43:47 »
Does the key operate properly,or is it loose?
Could be the ignition switch,/key lock ? when I first had mine,the key would fall out as I drove along a bunpy road,and the car kept going.You could also start it with a screwdriver : not good security.A new key lock barrel fixed it, costly though !

Paul
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biffabeau

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Re: Car wont turn off
« Reply #2 on: July 25, 2019, 12:22:00 »
My key had never fallen out. I would not say it is loose, but it certainly is not tight.
Problem if I change the lock, I'll end up changing them all?

WRe

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Re: Car wont turn off
« Reply #3 on: July 25, 2019, 13:08:36 »
Hi,
does your engine run switched off with one door open?
If so see this https://www.sl113.org/forums/index.php?topic=20425.msg144694#msg144694 and check your brake fluid.
...WRe

Pawel66

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Re: Car wont turn off
« Reply #4 on: July 25, 2019, 14:06:52 »
My key had never fallen out. I would not say it is loose, but it certainly is not tight.
Problem if I change the lock, I'll end up changing them all?

biffabeau, I think it may still be far from conclusion on lock change.

Assuming it was ok before and that the issue is that you have power on connector 15 on the ignition coil after the key is turned off, I looked at the wiring diagram and there may be several points where the circuit 30 (constant power) and 15 or 54 (power after ignition) meet:
1. By design, as per WRe post, fluid level control circuit and door switches circuit
2. By accident, when e.g. one of the wires gets lose. I have never experienced this kind of situation as yours, but if it did happen to me, I would probably look at going along circuits trying to determine where the short is (can be quite a few checks):
- do the blinkers work or e.g. wipers with ignition off?
- fuses 1 and 2 - are they sitting tight?
- If you measure with ohm meter - is there a short between fuse 1 and 2 brackets?
- Are the wires connected to them on both ends fitting tight where they are supposed to and none of them is lose and shorting fuse 1 to fuse 2?
- wires attached to ignition switch - are they sitting tight where they are supposed to or one of them is shorting pin 15 and 30?
- I would check with ohm meter if the ignition switch is ok - with key off or out - is there a connection in the switch between pin 30 and pin 15 - should not be; I think that if the switch is damaged, you can replace just the switch, not switch with lock. If the lock does ot turn the switch - this is another story.

Again, I am not sure if the above makes sense, but unless other more educated advise is provided - this is what I would look at. If I did not find anything - there would be further checks.

Just be careful and do not disconnect the battery when the engine is running to stop it, as you may damage VR, I think. Disconnect wire from connector 15 on ignition coil or any of the wires on the rsistor, I think this is best to stop the engine.
Pawel

280SL 1970 automatic 180G Silver
W128 220SE
W121 190SL
G-class

scoot

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Re: Car wont turn off
« Reply #5 on: July 25, 2019, 14:38:00 »
Engine is running ok until you go to turn her off. You can literally turn and remove the key and the engine continues to run.
For how long?  Until you find another way to shut it off?  Can you put the key back in the ignition and mess with the switch and get it to shut off or are you just stuck with a car that is still running....?
Scott Allen
'67 250 SL (early)
Altadena, California

Benz Dr.

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Re: Car wont turn off
« Reply #6 on: July 25, 2019, 16:20:49 »
This can be a dangerous condition and you should be very careful working around your car. I would get a new ignition switch. The keyed part is NOT your problem.
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Cees Klumper

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Pawel66

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Re: Car wont turn off
« Reply #8 on: July 25, 2019, 21:00:05 »
The switch for late 280SL, A 116 462 00 93, is available at the MB dealers (24hrs in my geography) for about $70.
Pawel

280SL 1970 automatic 180G Silver
W128 220SE
W121 190SL
G-class