automatic headlights

[elk_hunter]

Hi all,  First post for me.  

 

  After I get my truck fix(99 sierra 4.8),  8th cyl had no compression, found out the valve spring was broke, and the intake valve now wont seal all this at 53,000.  Dont see how this can happen at so low miles?   wonder if the piston slap cause this talking with gm now......anyways.

 

 Is ther  a way to disable the automatic headlights on my truck.  I can't due the dome light press 4 times. doesn't work on my truck.  I want to have controll of my headlights not the truck for driveins and such.  

 

Thanks for any help

 

[silverado man]

So you want to disable your automatic headlights on your 99 GM truck, eh? (I'm not talking about the DRL's)>>>

[ Follow Ups ] [ Post Followup ] [ VMag WWW Bulletin Board ] [ FAQ ]

 

--------------------------------------------------------------------------------

 

Posted by Neil99Z71 on March 27, 19100 at 14:21:14:

 

 

 

I just found this forum today and saw some old questions that have not been answered, so I thought I would help some of you out.

 

Listed below are the instructions that I came up with about a year ago to disable the auto headlights on the 1999 Silverado/Sierra new body style trucks. I have had

mine like this for nearly a year and it works great. There is a little work involved, but it sure beats

paying $90 for the little pushbutton gadget from R&D Truck Acc., (no offense Darrell). Keep in mind that I am talking about the automatic headlights (twilight sentinel) and NOT the #### DRL's!!!

Yes, I already know there is a fuse for the DRL's under the hood or you can just pull the bulbs out. Good luck and let me know if you

need any help. Later,

 

 

For those that don't know, the twilight sentinel is the feature that automatically turns on the

headlights and taillights when it starts to get dark outside. I like this feature alot, but I

wanted to find a way to disable it when hunting season comes around. I also like to use just

the amber colored running lights in certain situations. These instructions are for my new body

style '99 Silverado regular-cab, with LS option package.

 

There are two ways that you can do this procedure. The first one I have listed is how I did it

the first time not long after I bought my truck. The second way I have listed is how I did it a

few weeks ago just to see which way would be easier. I personally like the second way better,

but read both ways that way you will know everything that needs to be done.

 

Things needed are: One 1.5K ohm 1/2 watt resistor (Radio Shack, $0.49 for a package of 5),

electrical tape, pliers, and having small hands is a plus. A small socket set with ratchets &

screwdrivers will come in handy too. Another nice tool to have is a dental pick. It makes

unplugging the connectors a lot easier.

 

Here is the first way:

 

#1. First thing to do is to pull off the face of the dash and get it out of the way. It just pulls

right off and snaps back on, no screws, bolts, or anything like that. It helps to lower the

steering wheel all the way down and if you have an automatic, put the shifter all the way down

into 1st. Be sure to set the parking brake, just in case! Next, pull out the radio, (push down

on the two black tabs that are kind of sticking out on each side & pull the radio towards you at

the same time), and unplug the connector and antennae and set it out of the way. You should

be able to see the bottom of the ambient light sensor that is near the front of the dash,(it has

one gray wire and one white wire running to it). Try to twist the sensor to unscrew it from the

dash, (I had to use pliers from the top side on mine). Once loose, pull the sensor down from

the hole in the dash,(it can not be pulled through the top), unplug it from the the connector,

(not easy), and remove. Don't drop it or it might be lost forever down in the dash

somewhere. Now take the connector plug-in (the one with the gray & white wire) and route it

up through the hole in the middle of the dash for easier access to it. Now you can plug in the

resistor into the connector, (I found that it works best to fold the wires of the resistor over

itself once to be sure that the wires are making contact to the connector), and tape it up with

electrical tape. Be sure to test it out to make #### sure that it works, (hint: Release the

parking brake or else you won’t know if it is working correctly.). If it is not installed

correctly, the headlights & taillights will come on whenever the truck is turned on, day or

night. What you do next is up to you. You can either re-install the unplugged light sensor to

fill in the hole in the dash or leave it out and have a hole in the dash. Put the radio and dash

back in and your done!

 

I've had mine wired this way for months and have had no problems at all, it doesn't get hot or

anything and I have total control of the headlights.

 

 

The second way to do this is…….

 

#2. Another way to do this is to remove the whole upper dash unit. It really wasn't that hard

to do and it makes it ALOT easier to get to the ambient light sensor. You do not have to

remove the radio if you do it this way.

 

First thing I did was remove the face plate cover that covers the radio, gauges, etc. Then

removed the 5 nut screws that hold the dash cover to the instrument panel. Took out the

screws that are on each side of dash, (in the door jam areas, covered by the fuse panels).

Removed the plastic A-pillar covers, (they just pop out from the top, be sure to put the metal

clips back on the cover before re-installation). Got a butter knife and popped out the 2 A/C

vents on the passenger side and removed the 2 screws that are in the holes there. Pulled out

the "handle" that is directly above the passenger side airbag, (if you look inside the A/C vent

holes you will see a white plastic "clip" on each side that is holding the steel rods of the

handle, push these in slightly and pull the whole handle out). Double-check for any screws or

clips, just in case I forgot to mention some.

 

Now the hard part. You have to pull hard, straight back on the dash cover to get it out. I

started on the driver side and worked my way to the passenger side. I put one hand between

the bottom of the windshield and the front part of the dash in the driver side corner between

the windshield & bottom of the A-pillar and pulled it straight back to "unclip" it from the

metal that is holding it there. You have to use a little force to get it out, but you will hear and

feel it pop when it gets out of the first clip. There are 5 or 6 of the clips that the front part of

the dash needs to be “unclipped” from. There are also 3 small clips that hold the dash to the

top part of the passenger side airbag cover, they don't take much force to be popped out. The

airbag stays in place. Don't pull too hard or something might break that you don't want to

break. After you unclipped all of them, you can pull the dash back a few inches and flip it up a

little bit to get to the light sensor and unscrew it from the hole, (twist it a 1/4 turn). Then you

can take the whole dash completely out of the truck.

 

Unplug the light sensor from the connector with the white & gray wires. Put in the resistor,

tape it up, test it out and put everything back in the way it came out. Putting the dash back in

can be a little tricky. Make sure everything is lined up right and pop it back into place. Put

all the screws back in and snap everything else back on and your done!

 

I wish I would have done it this way the first time, it is alot easier than fighting under the dash

trying to unplug that #### sensor. You don't even have to take the radio out! I didn't break

anything while doing this and I was kind of rough with it at first because I wasn't sure how to

pull the dash out. It took me a little over an hour to do this, but I could probably do it in 15

minutes now that I know what to do.

 

Some truck owners have had to use different kinds of resistors, (different amperages,

wattages, Ohms, etc.), to be able to disable the auto headlights. Most owners, including

myself, have had the best luck with the resistor mentioned previously.

 

Some folks have added a toggle switch, or something similar, to the wires of the light sensor.

This way they can choose between having the auto headlights operational or have manual

control over them. I have not done this yet, but I will include some instructions of how I was

told to do this. These instruction were given to me by Chris Leigh, (Thanks Chris!). Here

they are:

 

“Neil,

 

Just get whatever type of two wire switch pleases you. Anything from the auto parts store will

do, if they don't have anything you like try a Radio Shack. Hook the resistor to the one of the

contacts on the switch, hook the other side of the switch to either of the sensor wires (white

or grey). [important note: If you solder rather than crimp connect be sure to use some type of

heat sink so that all the heat from soldering doesn't go into the resistor.] When the switch is

closed it'll work as it does now (manual mode). Open the switch and it should go into auto

mode. Mine was a little different (I have a 99 Silverado 2500) in that mine required two

resistors to allow for manul light operation and therefore the switch setup was a tiny bit

different. What I laid out for you is the setup for a 'one resistor bypass'. Mine has a bit of a

delay from the time you change the switch position to when the lights actually change mode. I

think this is something they build into the light relay to avoid inappropriate on-off action by

the lights……Chris”

 

Good luck & feel free to ask questions. Print this out so it is handy. My Email address is:

[email protected]

Later,

 

Neil

 

p.s. I might as well tell yall how to disable the DRL’s (Daytime Running Lights) too, because

I just know someone is going to ask.

 

There is a fuse for them in the “Electrical Center” that is under the hood on the drivers side.

It is a small, blue 10 amp fuse. Look under the lid to the electrical center and it will show

which fuse is the DRL fuse. Pulling this fuse does not affect any other accessories.

 

You can try this if you have some electrical experience.  Or you can buy this click here

[elk_hunter]

Thanks!!!

[sgiangregorio]

In my old 96 Blazer, putting on the Emergency Brake shut off the DRL. Don't know if it will help on the 99 with auto headlights, but worth a shot...

[sgiangregorio]

But to add to my previous post, obviously this would only work when at the drivein and not heading down the road.  

[sonjaab]

ELK.....Check out www.lightsout.org

Free and easy advise to shut off those

PIA auto ons and DRLs.  I used their

info to disable both in my 01...geo

[elk_hunter]

Well finally got my truck back from the shop.  I tried they parking brake, and gues what?   It DID NOT turn off the automatic head/tail lights.  

   So I guess i'll be duing the resistor fix for the sensor.   that is only may a $1 job. compared to the $90 for that kit.  And i'll decide if I want to add a switch to that resistor so that i can decide to use it in auto or manual mode.  

 

Thanks for all the replies and information you gave me!!

 

   

[nonstop]

That is one cool how-to.

 

Does anyone nowhere that switch (with the led) comes from?

 

Is it avaliable from the dealer?

[sonjaab]

NONSTOP.....That switch that fits in the dash

to shut off auto ons and DRLs is made by

R&D acessories about 80 bucks US.

www.truckautoaccessories.com

 

Or check out www.lightsout.org

for FREE easy advise to shut 'em off

.........geo

[sonjaab]

BTW:  Check out mountianeer toms web site

around here.  Hes got pics and instructions

for the R&D controller.  His web site is in his

profile.

[nonstop]

NONSTOP.....That switch that fits in the dash

to shut off auto ons and DRLs is made by

R&D acessories about 80 bucks US.

www.truckautoaccessories.com

 

Or check out www.lightsout.org

for FREE easy advise to shut 'em off

.........geo

sonjaab,

 

Thanks,

 

I saw the R&D switch, and was just asking if the dealer makes one like it.

 

Seems like a pretty slick fit if they(R&D) made it themselves.

[AZ-Z71]

Before you go pulling it apart use the parking brake to shut off the headlights while at the drive in.

 

I have the 99 and it works on mine.  If the truck is running and you put the parking brake on it won't work.

 

First put the parking brake on then start the truck and it should work for you.

[Firetiger(MN)]

Before you go ahead and remove the entire dash, this is how I did it.  Very quick and simple.

 

This is the way I did mine with no removal of panels needed. Very easy and quick.

 

I'll try to explain this as clear as possible, but if you have any questions feel free to mail me.

 

Basically you will need a pair of wire cutters and a 1.5K ohm 1/2 watt resistor that you can get at Radio Shack. Electrical tape and possibly some wire nuts will work to wire in the resistor. You can solder the wires if you wish.

 

You may want to remove the neg. battery cable to assure you don't do any unwanted damage to the electrical system. This is not necessary, but a good precaution to take.

 

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.

 

Located 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.

 

Clip these two wires that are coming off this plug (C3). Leave a few inches to work with. Tape up or place wire nuts over the other end of these wires that go up under the dash(they go to the light sensor). You have now removed the light sensor from the electrical system and is now just a dash orniment.

 

Connect the gray wire from the plug (C3) to one end of the resistor and the white wire to the other end. Make sure you tape up all wires to prevent a short. You should now have a gray wire coming from C3, going to one lead of the resistor and the white wire from C3 to the other resistor lead. Plug in C3 to the BCM and replace the neg. battery cable if you removed it. 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!

 

Shouldn't take very long after you find the wires which are right in front of you. Much easier and quicker than dismantling the entire dash to get to the light sensor! On my '99 I pulled the radio and reached my hand up to the sensor. Very tight fit. On my '02, I found a brace behind the radio which prevented me from getting to the sensor. That's when I found this simpler procedure and did it in minutes.

 

Any questions, give me a shout.

[elk_hunter]

firetiger

 

 Thanks that seems a lot eaiser than taking the whole freaking dash apart.   Thanks for the info!!

 

 

[nonstop]

Ok not to beat a dead horse, but,

 

Does GM offer a pod switch, like the one shown, that some how could be wired with a 1.5k resister?