Headlight turn on without turning on light switch

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Road Trip

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The DRL control Module

In the previous reply I circled the name of the DRL Module. In the first attachment
I've added a .pdf page of the same thing so that you can blow it up in order to better
see the connection details.

Now that I had found this little bit of functionality in the wiring diagram, where would
I find this physically located in a real vehicle? Thanks to a fellow on YouTube who goes
by the name "Dr. Shock" he clued me in, which is a good thing, for the FSM was kinda
vague about the whereabouts of this widget:

You must be registered for see images attach

(credit: Screen grab taken from this VIDEO.)

If you want to know a lot more about the DRL module, where it lives, and what it's comprised of, I recommend following the link and getting your fill.

****

And that's pretty much all I've got for now. This is just informed guesswork, but it's entirely possible that
your DRL Module (being comprised of a bunch of surface mount components soldered to a small card) may have
changed it's behavior due to a significant jolt during the accident.

Some folks reading this would just get another card or two out of the treasure yard, and use whichever one works
the closest to correct. By the same token, there are those who would reflow the solder joints and see if they couldn't
get the original module to straighten up & fly right. Or even reverse engineer the card?

So, bringing all this back to your original post, my best guess is that this module could well be the root cause of the
behavioral changes you have observed.

Standard disclaimer: This is just food for thought, and not a guaranteed diagnosis. But if you eventually figure all this
out, it would be very cool if you were to report back with what was the final fix for this.

Hope this helps. Safe travels, either with or without your DRLs. :0)
 

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  • DRL module & wiring diagram.pdf
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delkaandrew

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The DRL control Module

In the previous reply I circled the name of the DRL Module. In the first attachment
I've added a .pdf page of the same thing so that you can blow it up in order to better
see the connection details.

Now that I had found this little bit of functionality in the wiring diagram, where would
I find this physically located in a real vehicle? Thanks to a fellow on YouTube who goes
by the name "Dr. Shock" he clued me in, which is a good thing, for the FSM was kinda
vague about the whereabouts of this widget:

You must be registered for see images attach

(credit: Screen grab taken from this VIDEO.)

If you want to know a lot more about the DRL module, where it lives, and what it's comprised of, I recommend following the link and getting your fill.

****

And that's pretty much all I've got for now. This is just informed guesswork, but it's entirely possible that
your DRL Module (being comprised of a bunch of surface mount components soldered to a small card) may have
changed it's behavior due to a significant jolt during the accident.

Some folks reading this would just get another card or two out of the treasure yard, and use whichever one works
the closest to correct. By the same token, there are those who would reflow the solder joints and see if they couldn't
get the original module to straighten up & fly right. Or even reverse engineer the card?

So, bringing all this back to your original post, my best guess is that this module could well be the root cause of the
behavioral changes you have observed.

Standard disclaimer: This is just food for thought, and not a guaranteed diagnosis. But if you eventually figure all this
out, it would be very cool if you were to report back with what was the final fix for this.

Hope this helps. Safe travels, either with or without your DRLs. :0)
Wow that was a lot of interesting and great information! I will definitely refer back to your responses as I try to troubleshoot this in my free time!
I appreciate you and everyone else’s advice and comments and will get back to everyone if and when I find a solution! Thanks!
 

Road Trip

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Wow that was a lot of interesting and great information! I will definitely refer back to your responses as I try to troubleshoot this in my free time!
I appreciate you and everyone else’s advice and comments and will get back to everyone if and when I find a solution! Thanks!

No problem. I'll admit that I've never spent any time studying a DRL issue before today,
so it was a good excuse to familiarize myself with a rarely traversed area of the wiring diagrams.

And if you are able to come back and detail what changed state before/after the accident, then
no doubt this info will help others who are researching similar issues.

Best of luck with the hunt --
 

delkaandrew

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I never added a picture of the accident. But here’s one, definitely a great possibility that something got moved out of position from a near 60mph impact my windshield wipers also will turn on briefly when I drive over big bumps. That’s an issue for another day haha.

4 vehicle pile up, I was Vic #3. Cause of accident was detracted driver cut off Vic #1 and chain reaction followed.
 

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Road Trip

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Whoa. Looks like your truck did a good job of protecting you.

And as evidenced by the vehicle in the background, there was a lot of
kinetic energy involved. It was definitely not your time. Be sure to treat
every day as a present.

...and if we can figure out the DRLs then we can start in on the
'hit bump, get wiper' issue. There's plenty of talent in here with
experience sorting out flaky wipers.

Safe travels --
 

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Hola, I ve owned this K1500 96 suburban for 6 years, always run with the lights on, even with the light switch in off. Like 10 mins ago, a convenience center cable was cut (DRK GNT) and the front lights are working only when switch on, as it supposed to be. :)
Now I am looking if other systems were affected

R.
 
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