Automatic headlights
Thread Starter
Junior Member
Joined: Oct 2020
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Are you sure it's not the daytime running lights that are the problem and not the automatic headlights?
If DRL's are enabled, you get low voltage on the low beams and most LED's have a voltage range they need to turn on, not sure what yours might be....and also with most you either get off or on, not dim unless you have an additional driver or something.
When dark the low beams are switched to full voltage for automatic headlights, headlight icon comes on. When light they switch back to low voltage for DRL's, headlight icon goes out.
I turned my DRL's off in the dash menu after installing the LED"s. Didn't know if they'd function or not and didn't bother testing.
With forscan you can switch your DRL's to fogs or other lamps if you want to retain the function.
If DRL's are enabled, you get low voltage on the low beams and most LED's have a voltage range they need to turn on, not sure what yours might be....and also with most you either get off or on, not dim unless you have an additional driver or something.
When dark the low beams are switched to full voltage for automatic headlights, headlight icon comes on. When light they switch back to low voltage for DRL's, headlight icon goes out.
I turned my DRL's off in the dash menu after installing the LED"s. Didn't know if they'd function or not and didn't bother testing.
With forscan you can switch your DRL's to fogs or other lamps if you want to retain the function.
That is definitely something I can check today but why would that cause only 1 side to stay on while the other turns off?
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Joined: Dec 2013
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From: SC
Easy way to see if it's the DRL's or not is to put it in automatic and if you have the one headlight on deal, set the parking brake which turns off the DRL's.
Last edited by SSellers; Oct 10, 2020 at 01:02 PM.
Thread Starter
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Ok so, I'm I'm the sunshine and the headlight symbol on the dashboard is off. The drivers side headlight remains on. I applied the parking brake and nothing changes. The light goes off when I put the truck in park but comes right back on when I shift out of park.
I could switch the bulbs around and see if the bulb itself is the issue but it's a pain in the butt channing headlight bulbs on these trucks. If there is a part I can test or change out I'll try that but if not I guess I'll just cover the sensor and run headlights and fogs at all times.
I know a BCM was mentioned, but I don't know what that is.
I could switch the bulbs around and see if the bulb itself is the issue but it's a pain in the butt channing headlight bulbs on these trucks. If there is a part I can test or change out I'll try that but if not I guess I'll just cover the sensor and run headlights and fogs at all times.
I know a BCM was mentioned, but I don't know what that is.
5 Year Member
Joined: Feb 2019
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I'm sticking with my guess I posted at #7 and the follow-up #10 post it's the daytime running lights messing you up. My OEM lights go off in Park during the day, then come back on when shifted to drive
https://holdcycorp.com/led-headlight...sion-problems/
https://holdcycorp.com/led-headlight...sion-problems/
Last edited by MikeD134; Oct 10, 2020 at 03:25 PM.
5 Year Member
Joined: Nov 2018
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From: Calgary, Alberta
The BCM is the Body Control Module. It is what the interior passenger side fuse panel is part of. It controls all lights and many, many other functions. You need to check the appropriate pins on the BCM to see if it is providing the power to turn the light on in DRL mode. There are separate circuits right from the BCM for left and right hand headlamps.
Note that you need to be absolutely sure if that is the problem. It is pricey to buy and needs to be programmed for your truck.
Have you switched the bulbs left to right to see if the issue follows the bulb?
Senior Member
Joined: Dec 2013
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From: SC
Depending on year and what dash display you have, you can go to the lighting section there and turn off the daytime running lights. It's pretty obvious that's what it is.
I don't think you can do it on the base display.
I don't think you can do it on the base display.
Last edited by SSellers; Oct 10, 2020 at 04:36 PM.
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From: Chicago area
Ok so, I'm I'm the sunshine and the headlight symbol on the dashboard is off. The drivers side headlight remains on. I applied the parking brake and nothing changes. The light goes off when I put the truck in park but comes right back on when I shift out of park.
I could switch the bulbs around and see if the bulb itself is the issue but it's a pain in the butt channing headlight bulbs on these trucks. If there is a part I can test or change out I'll try that but if not I guess I'll just cover the sensor and run headlights and fogs at all times.
I know a BCM was mentioned, but I don't know what that is.
I could switch the bulbs around and see if the bulb itself is the issue but it's a pain in the butt channing headlight bulbs on these trucks. If there is a part I can test or change out I'll try that but if not I guess I'll just cover the sensor and run headlights and fogs at all times.
I know a BCM was mentioned, but I don't know what that is.