Automatic HeadLight Diasble

[thechevyhdman]

I have the info to override the auto headlights but was thinking of an easier way. When we hit our dome override button it shuts down the AH. Now that works until you shut down the truck and restart AH works as it should. Now I assume that the headlight switch must "know" when the truck is shut down to return to normal. Is it possible to run constant power to whatever "controls" the headlights from coming on automatically to fool it, and make it think the truck was/has never been shut down? Like I hit the dome override....wire whatever controls the AH from coming on/off to a constant 12V power source, and never have to hit the DO again. Basically just fooling it into thinking the truck is constatly running and never shut down?
Is this possible, or am I smoking crack?

[DmaxMaverick]

All of the lighting relays are controlled by the BCM. That is why they dim or turn off after a while to prevent battery drain, and are also effected by ignition switch and door.

Because it is part of the BCM programming, theoretically, a person should be able to "program" it to do whatever. There is a possibility that a pin at the ECM could do it with a key cycle. The features may even be accessible with a Tech II. Best approach may be to just go to a familiar dealer and have a talk with one of the nerds, or perhaps JK could find it.

The 2003, on the other hand.....
May be either more or less difficult.

Good luck!

[1BADDMAX]

On my old Z71 (1999 new body style) I put a 1.5k resisor in line to replace the sensor in the middle of the dash. I tried to do the same on my 2001 2500HD, but I can't get my hand back there. If someone with a service manual could tell me where those wires go I could just splice it there.

[Silver Bullet]

I am in complete control of my headlights...

truckautoaccessories.com

see pic in sig...

[FirstDiesel]

Steve

Is your website out. All I get is page not found.

Never mind! smile.gif

[ 03-31-2003: Message edited by: FirstDiesel ]</p>

[Silver Bullet]

First - Must be a user error!!!! :D

[1BADDMAX]

I disabled my automatic headlights for good last night. If you look under the steering column there are three plugs (BCM). Unplug the purple labeled plug and find A4 and A6, they are white and gray wires. Cut these wires and solder in a 1.5k resistor. Those two wires go to the photocell on the dash, but I couldn't get my hands back there to unplug the connector. NO MORE automatic headlights. I got tired of hitting that dome override button. I know for a fact this works on 1999-2002 trucks. I'm not sure about the 2003 wiring architecture.