NBS automatic light question...

[The Raven]

GMT900 guy here, stopping by with a question for you GMT800 guys...

Do you have the over-sensitive auto-light sensors that us 900 guys have? I'm thinking about trying a cheap little experiment with mine because i'm tired of my headlights (now more expensive retro'ed LEDs) coming on when the sun is still blaring at 7PM in the summer. This also causes my dash lights to dim and my infotainment screen becomes unreadable. I'm going back a generation to see if the GMT800 trucks do this too. If not, i'm going to order a sensor from a 2002 and try it out. Might work, might not.

Thanks!

 

[Doubeleive]

does your dimmer switch work? also the radio has a brightness setting, the sun sensor is likely the same part number. are you worried your led's might wear out? they shouldn't and they should last for many many years if there any good.

 

[The Raven]

does your dimmer switch work? also the radio has a brightness setting, the sun sensor is likely the same part number. are you worried your led's might wear out? they shouldn't and they should last for many many years if there any good.

Dimmer switch works fine. I'm very happy with my radio brightness settings for both day and night...I just need the truck to stay in "day mode" during the day. When it switches to "night mode" it turns on the headlights unnecessarily, dims all the interior lighting to night mode - which makes my infotainment screen appear blank through sunglasses (which i'm wearing because it's bright as hell outside), and also reduces the effectiveness of the automatic A/C (cause it thinks there's less sun-load).

I looked into it...the part number for the sensor for GMT900 trucks is 13498958. The part number for GMT800 trucks is 12450120. They are very different sensors and I found that I actually have had the GMT800 sensor in other GM cars i've owned, and they haven't displayed the behavior that my Tahoe does. The only remaining question is whether or not it makes a difference...GM is very unpredictable with this stuff...it could be a very simple setup that depends completely on the sensor, or it could be that all the sensors work exactly the same way and the differences are in the BCM. I know the only way i'm going to find out for sure is to try it. But I figured if the GMT800 trucks have the same issue that the GMT900's do, then this is a dead end from the start.

 

[HiHoeSilver]

Can't speak to the differences. However, my gmt800s seem to switch reasonably, imo.

Also, is your windshield tinted? Or the lens dirty or scratched? Anything that would make it think it's darker than it really is?

 

[Doubeleive]

I went from a 00 to 12, (I also have a 03 Silverado and 04 burb) in my opinion they behave the same, although the 2012 sensor is set deeper in the dash, if I were to attempt to change anything I would try to get the sensor up higher more level with the surface of the dash it may not even be possible though depending on the design I haven't really looked that close I just noticed it is inset a bit compared to the nbs sensor. my 2012 is also a yukon and the yukon does not have a dedicated drl so the low beam is on 24/7 I also have a aftermarket headunit and I just turned off the automatic dimming. so the only difference I ever notice is if the interior lighting is lit or not. cluster is always lit and I have the dimmer set at max so nothing ever changes.

 

[The Raven]

Windshield not tinted, no scratches or anything like that. I actually even tried replacing my sensor with a new one thinking maybe they wear out, but no change. It's either that the sensor is too sensitive or the BCM code for this function is written on the ultra-safe side. So I figured i'd try this little experiment and then if nothing else i'll just disable automatic lighting. I will also pose the issue to a BCM hacker to see if they have any tricks but I think that's unlikely to go anywhere.

 

[adventurenali92]

I feel like my 2006 sensor is a bit touchy. If i sit at a stop light under a freeway bridge or shady spot for more than a minute or two it’ll kick on my lights. If I’m parked in the shade in the late afternoon at work and start up, they will kick on. But then other times I think they will come on and the don’t. It’s weird... lol

 

[The Raven]

Yeah from the responses i'm getting and what i'm reading elsewhere it appears that the GMT800's are the same. I guess it's just the way the BCM is programmed. I will run it by a BCM hacker and then probably just end up disabling automatic lights.