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Wink Is it a bug...or is it a feature? (electrics)

Bug/Feature #1 - It all started when I swapped my H5s for H4s (big improvement!) on my '83SC this summer, and of course I also added the headlight relay from our host.

A few night drives later, and a bit more humid than usual, I arrived at my destination, and turned the key to shut the car off...and nothing (meaning, the car was still running, even with the key out). What?!? Imagine you opened a tin can that read "beans" on the outside, and found peas in there instead. Yes, I had that look on my face...

Then, on a whim, I reached over and shut off the rear defogger...and off went the engine.

Now, my daughter loves taking a night drive with me - I keep the lights and defogger on, pull into the garage, and take the key out of the ignition - but she gets to turn the car off via the defroster switch!

Now, I love any chance to delight my 11 year old daughter (I know those chances will slip away as she hits teenager-dom) but even I know this is not normal P-car behavior. That said - is this anything to be concerned about?

Bug/Feature #2 (somewhat related) - I now notice that when I am running high beams, the fogs will not come on (I can pull the fog switch and the fog switch light won't even come on; as soon as I shut off the high-beams, the fogs come on as does the switch light). Is this a feature that follows the "if the fellow behind the wheel is using high-beams, there's no need for fogs" rule (that I just concocted) or is this behavior not normal?

Thanks for weighing in, Pelicans!

Old 10-06-2014, 06:45 PM
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Fog light behavior is normal.

Car continuing to run with defrost on is very abnormal.


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Old 10-06-2014, 07:02 PM
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I think that you have some wires crossed in your two bug/features. Looking at the Haynes 1982 schematics the electronic ignition and the power for the rear window defogger switch are supplied by the same terminal on the ignition switch. In your case the power for the electronic ignition is being supplied thru the rear defogger switch.

The second bug/feature is normal since the fog lights should only come on with the fog light switch turned on and the low beam headlight switch on. When you select high beams the fog lights are disabled.

I would recommend that you disconnect the battery and due a point to point continuity test with an ohmmeter of the ignition and defroster circuits. You might find that either someone has reconnected the wires wrong. In any case I can't see how a shorted or open wire would cause the symptoms you are having but I would not say that its isn't possible.
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Last edited by targa80; 10-06-2014 at 07:29 PM..
Old 10-06-2014, 07:24 PM
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I agree with Targa80 on the approach to sorting your problem.

However! I had another thought... Did a PO wire up the rear defog switch to act as a Kill Switch hidden in plain sight?

Will the car start with the rear defogger turned off? Or on?

Just a thought.

Cooper
Old 10-06-2014, 08:49 PM
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If I had to guess, you disconnected too many wires.... and put them back in the wrong place when you wired up your headlight relay.....I think you will find that targa80 is right.
Old 10-06-2014, 09:23 PM
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Quote:
Originally Posted by Cooper911SC View Post
I agree with Targa80 on the approach to sorting your problem.

However! I had another thought... Did a PO wire up the rear defog switch to act as a Kill Switch hidden in plain sight?

Will the car start with the rear defogger turned off? Or on?

Just a thought.

Cooper
The plain-sight kill switch would be a super-slick solution for theft-aware owners! I will take a look and report back. The car definitely starts with the defog off.
Old 10-07-2014, 04:13 AM
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if it did not do this before the H5 change out, then go back to all the places you changed wires or worked on. check your wiring for the relay. did you mess with the ignition switch, headlight switch.

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Old 10-07-2014, 05:01 AM
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