Why does the engine stall when I turn on the headlights?

1998 PLYMOUTH NEON
180,000 MILES
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WCKNOWLES
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I can turn on the heat, AC, radio and the parking lights with no problem but as soon as he headlights come on it stalls. It does this only when the headlights are switched on with or without anything else on.
Dec 28, 2011 at 7:59 PM
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SATURNTECH9
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Sounds like the head lights are stealing ground from another circuit cause the car to shut off.Do you have a multimeter to do some testing?
Dec 28, 2011 at 8:11 PM
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WCKNOWLES
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Yes I do. As a matter of fact I check the alternator and battery first.
Dec 28, 2011 at 8:18 PM
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SATURNTECH9
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Do you have daytime running lights?
Dec 29, 2011 at 1:44 AM
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WCKNOWLES
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No daytime running lights or fog lights.
Dec 29, 2011 at 2:26 AM
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SATURNTECH9
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Alright the black and orange wire going to the head light switch unplug that connector.Now see if you have 2 ohms or less to ground.Do the same with the head light bulbs and check the black wires and make sure they have 2 ohms or less to ground.
Dec 29, 2011 at 2:46 AM
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WCKNOWLES
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Ok I have checked all the wires you suggested and all were 2 ohms or less. After putting everything back together I was able to start the car and everything worked normally, lights, heat, AC and radio. After trying everything a few times it did stall when the heater fan was turned on one time but started right up after. I did notice however the the negetive battery cable was getting warm. Could all of these problems be caused if the negetive cable from the battery was bad? I think the may be original to the vehicle.
Dec 29, 2011 at 6:10 PM
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SATURNTECH9
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Alright heres the next thing i want you to test ground the black lead from the meter to the engine block.Then disconnect the negative battery cable from the battery.Inspect it for loose connection to the battery and corrossion.Now hook the red meter lead to the negative battery cable end that goes to the battery.Do you have 2 ohms or less?
Dec 29, 2011 at 6:53 PM
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WCKNOWLES
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Yes my reading bounced around a bit but when it settled down it was under 2 ohms.
Dec 29, 2011 at 7:49 PM
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SATURNTECH9
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What kind of bouncing around how high did it go before it settled down to 2 ohms or less?Sounds like you might have to check that cable out better it should just read 2 ohms or less.Also check the case of the alternator to the engine block see if you have 2 ohms or less.
Dec 29, 2011 at 7:56 PM