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Old 03-17-2016, 10:56 PM   #1
klwebb
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Key doesn't shut off engine..???

Soooo today I was trying to figure out my taillight I had them all taken apart. I went to start the truck and it started GREAT then came time to turn it off and turning the key did nothing?? The key was OUT! I had to disconnect the battery to get it shut off. Any idea what's up?? We put a new starter in it on Tuesday but it has been started/shut off since then.
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Old 03-17-2016, 11:23 PM   #2
lutronjim
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Re: Key doesn't shut off engine..???

Not sure about your model but some are wired with a wire to the coil from the starter relay bypassing the dropping resister fed by the switch. This gives the coil a higher voltage for starting. Make sure that feed is not hot with the switch off.
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Old 03-18-2016, 09:49 PM   #3
kajf9491
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Re: Key doesn't shut off engine..???

I had a similar thing happen to me last week. I was working on the truck all day with no issues, and while trying to start it, the starter solenoid starting rapidly clicking. I turned the ignition to off, then pulled the key out and the solenoid continued to click away. Only way I was able to get it off was to disconnect the battery. I went through and pulled the starter out and tested the solenoid and everything seem to check out alright. I then pulled the ignition switch apart and checked continuity and voltage. Again everything checked out. Put the switch back together, reconnected the battery and I haven't had the same issues again. I'm wondering if it is a grounding issue if that's possible.

Have you been able to come up with a fix?
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Old 03-20-2016, 12:50 PM   #4
mtdave2
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Re: Key doesn't shut off engine..???

had this happen a few times. first one the neg battery cable had was grounded on the exhaust manifold, not sure why that would be a big deal, but once i moved it off...all good. that truck had all sorts of odd electrical issues
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Old 03-20-2016, 02:37 PM   #5
Tomahawk30
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Re: Key doesn't shut off engine..???

Be real careful when you start running into issues like this. I had one do this shortly before the ignition switch basically fell apart inside. It can short things out pretty quickly. I melted some wires pretty badly on one of the trucks I had that way, but was able to pull the battery cable before things REALLY got bad. I've actually had two different worn out ignition switches that wouldn't release the starter as well (after the truck was running, the starter motor stayed engaged until I pulled the battery). I'm to the point now that I just immediately replace the ignition switch and replace the battery cables on every new truck I get as a precaution. Might be moderately paranoid about it, but better than the alternative!
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Old 03-20-2016, 02:45 PM   #6
davepl
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Re: Key doesn't shut off engine..???

I was trying to get my Range Rover's driving lights to come on like DRLs, and after wiring it up, if you had the manual switch for the lights on the vehicle would keep running. If you backfeed power accidentally into the ignition circuit, that'll do it.

In my case it even cranked when you hit the switch! Obviously I didn't leave it that way...
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Old 03-20-2016, 07:42 PM   #7
klwebb
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Re: Key doesn't shut off engine..???

Well, I figured it out.... When the light switch is pushed in the key works normally. On off, everything works. But when it's pulled out the key works to turn it on but not off. As soon as I push the button in it shuts it off? Weird but it works haha! I'm still looking for alternatives to blinkers
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18 year old girl who loves old trucks
•Previous Projects•
1971 c10 longbed 350/350
1977 Silverado longbed 350/350
1978 K10 shortbed 350/t400 lifted 6 inches on 33s
"LONGBED LIVES MATTER"
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Old 03-20-2016, 09:09 PM   #8
davepl
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Re: Key doesn't shut off engine..???

So you've somehow got power (or perhaps ground) feeding from the headlight switch to the ignition switch?

Only you know what you've done, unless its been like that since a previous owner.
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