Driver side headlamp doesn't turn on when running
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CF Beginner
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Driver side headlamp doesn't turn on when running
I have a 2010 Chevy cobalt. When I unlock it with the keyfob, both headlamps turn on. When I turn the car on, the driver side lamp turns off.
I tested the fuses and there is no issue. I swapped out the lamp and I still haven't fixed the issue.
Does anyone have an idea of what I should be looking for- wiring harness issue?
I tested the fuses and there is no issue. I swapped out the lamp and I still haven't fixed the issue.
Does anyone have an idea of what I should be looking for- wiring harness issue?
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so left daytime running light is out
-everything works with the full light system turned on; highbeam and low beam?
you checked the low beam fuse for each headlamp? cause the dtrl for the left headlamp runs thru both the right and left low beam fuses. the dtrl right side will work even if the right low beam fuse is blown
-everything works with the full light system turned on; highbeam and low beam?
you checked the low beam fuse for each headlamp? cause the dtrl for the left headlamp runs thru both the right and left low beam fuses. the dtrl right side will work even if the right low beam fuse is blown
Last edited by tech2; Mar 16, 2018 at 10:23 PM.
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my diagram shows no dtrl module....the bcm turns on the dtrl relay...one feed from the relay supplies both lights so bcm and relay are working. if the right dtrl is turning on the problem is the wiring to the left light or, right or left low beam fuse.
CF Beginner
Joined: Jun 2018
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From: Ontario
Your right tech2. My apologizes.
by the looks of it the low beam and high beam relays power both the head lamps simultaneously.
however there is a
Left Hand Low Beam fuse
Left Hand High Beam fuse
Right Hand Low Beam fuse
&
Right Hand High Beam fuse
all 10amp
there is also a high beam resistor.
by the looks of it the low beam and high beam relays power both the head lamps simultaneously.
however there is a
Left Hand Low Beam fuse
Left Hand High Beam fuse
Right Hand Low Beam fuse
&
Right Hand High Beam fuse
all 10amp
there is also a high beam resistor.
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Joined: Mar 2011
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I'm not seeing a resistor for the high beams?
the dtrl are run throught the low beams and most likely pulse width modulated to create a dimmer light output.
Last edited by tech2; Jun 11, 2018 at 7:52 PM.
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CF Beginner
Joined: Jun 2018
Posts: 16
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From: Ontario
I will post a photo of my diagram tonight after work Tech2. I didn’t study it to an extreme, but I do see a high beam resistor.
You are correct in saying that the DRL are powered through the low beam side
You are correct in saying that the DRL are powered through the low beam side