Disabling Auto Headlamps Gmt800

nick-o · March 22, 2011

OOPS. Somehow I distracted myself in the DRL direction. Sorry about that. So, here's the other circuit you need for that. Same principle except you want the C2 plug-pin A11 (white wire). The switch will provide a way to open the circuit and your auto headlights will not work. Close the circuit and they'll work normally. Your dash light switch will still work like normal.

Headlamp_Circuit.pdf

Thats what i was looking for. Ill try that sometime this week if i get a chance. Thanks allot

Digging up this older thread. Just wonering how this worked out if you tried it. Thanks for any info because I'm looking fo the same switchable setup.

Matt Fetters · March 22, 2011

To disable the auto headlights you need a 1.5K ohm resistor (Radio Shack) and 2 Scotchlok Tap Connectors (Walmart).

First locate the Body Control Module (BCM) which is under the dash, below the steering column. Laying on the floor, this should be visible without removing any dash panels. You should find a purple connector (C3). Unplug it.

Locate the white and gray wires (A4 and A6). I don't remember if white is A4 and gray is A6 or vice versa. It doesn't matter anyway. BTW - there are two gray wires in the connector. The one you want is the one farthest away from the white wire.

Tap the gray wire from the plug (C3) to one end of the resistor and the white wire to the other end. You don't need to cut the wires. Make sure you tape up all wires to prevent a short. You should now have a gray wire coming from C3 tapped to one lead of the resistor and the white wire from C3 tapped to the other resistor lead *. Plug C3 back into the BCM. Start the truck and make sure the lights are off. Throw a dark towel or something over the light sensor on the dash and verify the lights stay off. Try your light switch that has probably never been used and that's it! Takes about 5 minutes.

*You can add a switch here if you want. Just connect one end of the resistor to one of the wires in the connector (doesn't matter which one) and the other end of the resistor to one side of the switch. Then connect a wire from the other side of the switch to the other wire in the connector. This will allow you to turn Twilight Mode on and off

spock · March 22, 2011

you could just put you parking brake on one click and the auto lights will not work. the red brake light in your dash will be on, but the auto lights will be off

Should depressing the park brake pedal disable them on a 2004? I tried and it won't work for me. I like the auto headlamp feature, I just find it annoying when they come on when I start the truck in the AM.

brandon_guzzo · March 23, 2011

you could just put you parking brake on one click and the auto lights will not work. the red brake light in your dash will be on, but the auto lights will be off

Should depressing the park brake pedal disable them on a 2004? I tried and it won't work for me. I like the auto headlamp feature, I just find it annoying when they come on when I start the truck in the AM.

It should work. Try shutting the truck off and putting the parking brake all the way on then restart it to see if the headlights come on. What I finally did was tapped a resistor into the photo cell sensor and put a toggle switch on it so when the toggle switch is toggled on the headlights stay off, but when toggled off they go back to the auto feature.

brandon_guzzo · March 23, 2011

OOPS. Somehow I distracted myself in the DRL direction. Sorry about that. So, here's the other circuit you need for that. Same principle except you want the C2 plug-pin A11 (white wire). The switch will provide a way to open the circuit and your auto headlights will not work. Close the circuit and they'll work normally. Your dash light switch will still work like normal.

Headlamp_Circuit.pdf

Thats what i was looking for. Ill try that sometime this week if i get a chance. Thanks allot

Digging up this older thread. Just wonering how this worked out if you tried it. Thanks for any info because I'm looking fo the same switchable setup.

Yes I actually did it this last weekend and it worked perfectly. Matts description is exactly how I did it and I added in the switch so I can still use the Auto feature.

nick-o · March 23, 2011

OOPS. Somehow I distracted myself in the DRL direction. Sorry about that. So, here's the other circuit you need for that. Same principle except you want the C2 plug-pin A11 (white wire). The switch will provide a way to open the circuit and your auto headlights will not work. Close the circuit and they'll work normally. Your dash light switch will still work like normal.

Headlamp_Circuit.pdf

Thats what i was looking for. Ill try that sometime this week if i get a chance. Thanks allot

Digging up this older thread. Just wonering how this worked out if you tried it. Thanks for any info because I'm looking fo the same switchable setup.

Yes I actually did it this last weekend and it worked perfectly. Matts description is exactly how I did it and I added in the switch so I can still use the Auto feature.

Awesome Thanks!

FREERSY · March 29, 2011

Today i've tried both of the ways that were given. I used a jumper between the white and grey wires on C3 with a switch and 1.5k resistor like what matt had said and nothing happened when the switch was flipped. i've just tried the switch on the white wire on C2 by splicing in the switch and now when the switch is flipped and the dash switch is on O or parking lights only the parking lights are on with the blue highbeam light on in the dash. when the dash switch it moved to the hi/low position the hi/lows come on. i have a 01 sierra 1500 so i'm a little confused how some are getting this to work.

OOPS. Somehow I distracted myself in the DRL direction. Sorry about that. So, here's the other circuit you need for that. Same principle except you want the C2 plug-pin A11 (white wire). The switch will provide a way to open the circuit and your auto headlights will not work. Close the circuit and they'll work normally. Your dash light switch will still work like normal.

Headlamp_Circuit.pdf

brandon_guzzo · March 29, 2011

When I did mine I tapped both wires A4 and A6 then I attached one end of the two wires to each end of the resistor. I put the switch inline to open and close the circuit.Mkae sure its the C3 connector (purple connector) Here is a quick diagram kindda choppy but hope it helps.

f.tiff

FREERSY · March 29, 2011

Ok thats what I had done. the white wire and the farthest grey wire. i used a 1.5k ohm resistor and there was no change when i flipped the switch. i still have the switch hooked up inline with the white wire A11 on C2 like what was said at the beginning of the topic. hopefully it goes back to normal when i take that out and get it crimped back together

FREERSY · March 29, 2011

just went out and took the switch out from the white wire A11 on C2 the light blue connection and things look like they are back to normal except no drl on the front or rear. i can't remember if any lights are on on the rear with the drl on

anyone have any insight to why those aren't working now?

brandon_guzzo · March 29, 2011

There is no light that should be on with the DRL in the rear that I know of. Did you check the fuses for the DRL under the hood maybe one of those could have blown. You probably already know this but the truck has to be in R,N,D,1,2,3 not park for the daily running lights to come on and the parking break must NOT be on. Good luck

EDIT: I noticed in your post you said C2 connector. Both A4 and A6 wires are located on the C3 connector. So that may be the main problem on why it is not working. Also when you flip the switch there is a 30 second delay before they headlights will turn on or off.

FREERSY · March 29, 2011

yeah i had it on the c2 connector like what rmck490 said on the first page. i'll go have a look again and see if the drl are on but i'm glad that the other lights are working now

Edit: just checked the fuse and it was no good so i changed it and drl are back on. thanks guzz

brandon_guzzo · March 29, 2011

No problem glad everything is working again.

EDIT: If you try it again with the switch and resistor use the C3 connector (purple) and A4 and A6 wire, I can't see it no working. Good Luck

FREERSY · March 29, 2011

Alright i might try it again but that is how i first had it set up and nothing would change. maybe the taps that i used weren't close enough to cut into the wire on the truck. i was using the blue ones so i might have to try the next size smaller which is yellow i believe

govener71 · March 30, 2011

OOPS. Somehow I distracted myself in the DRL direction. Sorry about that. So, here's the other circuit you need for that. Same principle except you want the C2 plug-pin A11 (white wire). The switch will provide a way to open the circuit and your auto headlights will not work. Close the circuit and they'll work normally. Your dash light switch will still work like normal.

Headlamp_Circuit.pdf

Thats what i was looking for. Ill try that sometime this week if i get a chance. Thanks allot

On my 2000 Suburban all I had to do to disable the auto-on headlights was push the interior light on/off button four times in succession in six seconds to turn off the auto-on feature. This had to be done with the ignition on. When the car was turned off and restarted the auto-on was turned back on. Four pushes of the button turned it off again.

I think on this model of truck all you need to do is press the "dome override" button twice quickley while the ignition is turned on. Is should "ding" at you to let you know the code worked. If you press the button twice again the function will turn back on. This negates the need for re-wireing anything but you need to repeat this step each time you turn the vehicle on. It sounds like you are going way more in depth than I am explaining but that works on my brothers and friends 2000 sierra and silverado.