Rear Brake Light / 3rd Brake Light Problem

[mtesch]

I have a 2003 Silverado 2500hd with a brake light problem. The third brake light does not work when the brakes are applied. But... if I manually push the lever on my electric brake box, the third brake light works but my two rear brake lights don't. I've disconnected the brake box from the relay center with the same results. The trailer brakes also do not work with the brake pedal, but will work when the manual lever is pressed. Is there a seperate circuit for the third brake lamp?

[old dog]

check the chismal fuse (center high brake light )

I have a 2003 Silverado 2500hd with a brake light problem. The third brake light does not work when the brakes are applied. But... if I manually push the lever on my electric brake box, the third brake light works but my two rear brake lights don't. I've disconnected the brake box from the relay center with the same results. The trailer brakes also do not work with the brake pedal, but will work when the manual lever is pressed. Is there a seperate circuit for the third brake lamp?

[eweber64]

I have a 2003 Silverado 2500hd with a brake light problem. The third brake light does not work when the brakes are applied. But... if I manually push the lever on my electric brake box, the third brake light works but my two rear brake lights don't. I've disconnected the brake box from the relay center with the same results. The trailer brakes also do not work with the brake pedal, but will work when the manual lever is pressed. Is there a seperate circuit for the third brake lamp?

 

 

I have the exact same problem with my 2002 and am looking on here to find out what the issue is. I really need to get this fixed asap as I am pulling my 28 footer to Houston next month from St. Louis. Where is the "chismal fuse" located?