1986 740 GLE Ignition Cold Weather

Dec 09, 2005 3 Replies

In cold weather now it takes about 10 to 15 seconds when I turn the ignition key to ON for the instrument panel gauge lights to all light up. Once this happens then I can turn the key to START and the engine starts fine. If I just turn the key to START on a cold morning then the engine will crank for



10 to 15 seconds till all the instrument panel gauges light up and then the engine starts immediately. Does anyone know what is causing this slow start up with power I assume to the electrical system(relay?).

Thanks, Tom


It's gotta be an electrical problem, try wiggling the ignition switch, they've been known to go bad occasionally.

That's an excellent description of the symptoms I got when my '85 765T ignition switch was failing. It got worse over a period of a couple months until I got up the energy to change it. When warm it worked reliably. (You could pre-warm the switch with a hair dryer, I suppose, to confirm that is the problem. But I think it's a safe bet.)

The switch is easy to replace (up to an hour, if you work as slowly as I do, but nothing frustrating) and is available aftermarket for under $100 US from several sources - I went to IPD at

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Only the electrical part is replaced; you keep the lock part in place. IIRC a Phillips screwdriver does it all.

Mike

That's my first guess as well based on teh smptoms, but if it doesn't work...

...disconnect, clean, and reinstall the battery cables at both ends.

...Check the battery voltage before ignition is turned on, after it is turned on, while it is cranking, and after it starts.

....remove, clean and replace the fuses. A piece of scotchbrite works well. Clean the fuses AND the tabs where they connect in teh fuse box.

__ __ Randy & \ \/ /alerie's \__/olvos '90 245 Estate - '93 965 Estate "Shelby" & "Kate"

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