Author Topic: ignition ?  (Read 177 times)

William Dabney

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ignition ?
« on: October 12, 2019, 21:19:59 »
i own a 1968 250 sl . sometimes when i turn the key in the ignition the engine fires right up. other times nothing happens. i turn the key on ad off ad also jiggle the gear shift knob (automatic transmission). eventually it works. does anyone know if this is a key/key switch problem or is it something  to do with the gear shift knob?   TIA, bill Dabney

Cees Klumper

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Re: ignition ?
« Reply #1 on: October 12, 2019, 23:33:28 »
In my car's case, the same symptoms were caused by a faulty ignition switch, the electric rotational switch that plugs onto the back of the ignition lock. It was a bear to install as half the dash needs to come apart, but now the car starts properly, every time. In my case, the problem slowly got worse and worse over the years, until the switch stopped working altogether. I installed a separate start switch, which worked fine, but it always bothered me until I finally took the bull by the horns this summer.
I paid something like €70 from I think an Ebay vendor in Germany.
Cees Klumper
1969 Mercedes 280 SL automatic white

Cees Klumper

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Re: ignition ?
« Reply #2 on: October 12, 2019, 23:35:01 »
P.s. your issue may be caused by the start (inhibiting) switch on the firewall that is connected to the transmission via a cable.
Cees Klumper
1969 Mercedes 280 SL automatic white

Charles 230SL

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Re: ignition ?
« Reply #3 on: October 13, 2019, 18:03:45 »
hello Bill, I had the same problem a few years back with my 230SL - intermittent starting was a result of a worn contacts in my ignition switch. The switch simply got old and the internal contacts wore out.

I bought a NOS switch from a vendor on Ebay for about $200.00 USD. The switch is held to the back of the ignition lock with three screws.  There's a lot of good info on this forum about replacing the switch.
Switch Part Numbers:
000 462 06 93 (all 230 SL & 250 SL up to Chassis No # 002979)
116 462 00 93 (all 280 SL & 250 SL from Chassis No # 002980)


« Last Edit: October 14, 2019, 00:30:06 by Charles 230SL »