Ambers is the popular conversion of changing out the white 4114K factory Daytime Running Lamps (DRL) to AMBER bulbs. This mod <modification> is popular in any Chevy Avalanche Club conversion used to identify other club members. It is also really neat-looking, PLUS it is actually a safety enhancement as amber light is visible at a further distance. (Amber is the color to which the human eye is most sensitive.) Some vehicles such as Corvettes, Buicks and Chevy Vans are factory equipped with Ambers. However, check your local laws as some localities are very specific about what you can and cannot do as far as making changes to automotive lighting.
Now on to accomplishing the AMBERS mod.
If you have the plastic skirting all around your Av, you have a CLADDED (aka Body Hardware) Av. If you have NO CLADDING you have a WBH or- Without Body Hardware Av. (GM terminologies.)
The procedure for changing the DRLs is different for each of the two models.
On the CLADDED Av, your DRLs are located within the lowest part of your front bumper and are the INBOARD lights (closest to the tow hooks.) Switch on your fog lamps while the LOW BEAM headlamps are on and the transmission is in PARK. The DRLs are the extinguished lights next to the fog lights. NOTE: The fog lights will normally switch off whenever the HIGH BEAMS are on.
On the WBH Av, your DRLs are located within the set of lights below the headlamps. The DRLs are the INBOARD lamps (closest to the grille.) Switch on your parking lights while the transmission is in PARK and the DRLs are the extinguished lamps adjacent to the parking lights.
Amber bulbs to purchase <for either model of Av> are Sylvania 3157/4157NALL. A pair can be obtained at certain auto parts stores for around $5.50 or so. Do NOT pay $10 for these bulbs, as some other parts stores (who will remain unnamed) charge.
CLADDED Avys. From beneath the bumper, depress the lock tab on the DRL socket and turn 1/4 turn, pull socket out of housing. Remove factory bulb and replace with the amber. Reinstall socket (turn to lock.)
WBH Avys. Open hood. Remove L shaped shiny aluminum retainer pins from the tops of left and right headlamp assemblies. Carefully lift assemblies up and out of the way. (Do NOT disconnect any of their sockets/wiring.) Reach down to the DRL socket and depress its lock tab, then turn socket 1/4 turn, pull socket out of housing. Remove factory bulb and replace with the amber. Reinstall DRL socket (turn to lock) and reinstall headlamp assemblies. You may have to fuss a bit when reinstalling the drivers side headlamp assembly as the wiring may need to be positioned to allow clearance. Very easy to do, just do not force anything. The headlamp retainer pins may utilize a slotted tab at the top of the assemblies in which to lock the pins in place.
CHECKING YOUR DRLs.
BE FREAKING CAREFUL whenever you do this using method B!
Your DRLs will normally only be on in daylight (NOT inside your garage,) with the engine running and in DRIVE, NOT in PARK. The DRLs will switch off when the transmission is placed into PARK.
Method A) The safest method is to drive somewhere to observe the reflection of your Av in a glass window. Go to a local business, or convenience store (you need beer anyway, right?) Check DRL operation in drive, with the engine running, footbrake applied.
Method B) You can also check DRL operation by placing your Av in DRIVE on a flat, open area, and engaging the parking brake. Get out and observe the DRLs. DO NOT walk directly in front in case the brake slips. Or you can have someone stay in the drivers seat, depressing the brake pedal while you make your check.
Method B) is not recommended unless you live out in the boonies, as method A) is so easy and safe.
Method C) You can monitor DRL operation during the course of normal driving. At traffic lights you can often see a reflection off the back of a vehicle in front of you. This is an easy method for monitoring lamp status to determine a burnout. They should last quite a few years as the "NALLs" are long-life bulbs.
Follow up notes.
A) The amber bulbs will not burn your sockets or plastic lamp housings. When you go to change them from the factory bulbs, you may notice a very slight burnt look to the base of the sockets. This is noted to occur on the factory sockets with factory bulbs and is not to be of any concern to you. Lamp sockets which have just a little use (a brand new Av, for example, with only a few hours of running) may exhibit the slightly burnt-looking socket condition. Simply ignore this non-issue.
B) The description of how the DRLs and headlamps operate during daytime, as told in the above instructions, assumes that you have an original factory electrical wiring setup. Other modifications, such as Full Time DRLs (or All Time DRLs) and All Four-On High changes the way the DRLs and headlamps operate compared to the original factory set up.
You can do a search here to learn more about these additional modifications.
Thanx to avalanCHEVY for the writeup