I am new to this forum so I hope no one takes offense when I tell you that you DO NOT need to take your 03 Silverado to the dealer to flash the BCM or TBC once you properly install the factory fog light kit. How do I know this? I just installed the kit myself several weeks ago and I did not have to take it to the dealer. I also know other 03 Silverado owners posting on other Chevy Truck forums that have also installed the fog light kit and they did not need to take it back to the dealer.

There is a lot of misinformation floating around about this topic. First off, the instructions that come with the kit are written for earlier model years. Some of the information is contradictory. Specifically, the location for the connection in the wiring harness in the BEC is stated as D6 but the Figure Q contradicts this showing position A4. Be sure to insert it into D6. This is one of the pins of the relay you just installed.

My suggestion is to make sure you have a good ground. I highly recommend you drill a hole in the frame in a convenient location, clean off the undercoating to bare metal and then use a self tapping screw to secure the ground. If the fogs don't work after properly connecting them, CHECK THE GROUND.

While I have no experience with the earlier model year Silverados, I have heard that 02 and earlier models do require reprogramming. Since the instructions that come with the kit state to "Program the TBC to interface with the fog lamps." everyone believes this is required on the 03's. But remember, these instructions are written for the 02 and earlier models and not properly edited for the 03 model.

I apologize for the length of my post but I hope it is of some help to you. If you have any questions please let me know.

 

well I guess the '03s are the bomb

 

ok, heres the deal with the fog lights. THE INSTRUCTIONS SUCK!!!!!!!! I busted out the trusty old test light and if you unplug the harness under the fuse panel, point it away from you where you are looking at the wires going into the harness, there will be a red wire at the top of the harness and the feed wire for the lights plugs into the spot to the immediate left of the red wire. Oh, make sure you have a good ground, you cannot have any paint or that goo coating that GM puts on the frame and you should be good.

 

Welcome to LS1Tech Red Rado.

 

Red Rado quotes "While I have no experience with the earlier model year Silverados, I have heard that 02 and earlier models do require reprogramming." I should have made it clear that i was talking about the "old" body style(99-02).

The instructions are printed to be very general, so that GM can use the same instructions for many models and model years, if I'm not mistaken you will find the ame instructions if you were to buy fog lamps for and escalade or an avalanche