This 2001 Chevrolet Silverado came in the shop with the complaint of no stoplights. First I confirmed that none of the stoplights were working including the CHMSL (center high mounted stop light). After this I went to the underhood fuse box because the manufacturer has made diagnosing the stoplights very easy at this location. By going to the red, 10 amp, vehicle stoplight fuse, #17 and checking for power while some pushes on the brake pedal I can tell easily if the stoplight switch is good and I do not have to lay under the dash to do it. I identified the fuse location using the legend.
This one was really easy because when I located where the fuse was supposed to be I found that it was missing. I installed a new fuse and tested both sides for power while someone depressed the brake pedal. I found that the owner had been swapping fuses trying to keep his power outlet working for his cell phone charger.
If I had found power on one side of the fuse but not the other it would have indicated a blown fuse. If I had found no power on either side with the brake pedal depressed I would have suspected a faulty stoplight switch or no power to it and more testing would have been needed.
Luckily, the power supply fuse for the stoplight switch is the yellow, 20 amp fuse, #14 is right above the fuse I was testing. Testing here would have shown one of two things. Power on fuse #14 with no power on fuse #17 would indicate a faulty stoplight switch. If fuse #14 had been blown it would have indicated a short between the fuse and the stoplight switch and back to fuse #17. Also a blown fuse #17 would indicate a short between the fuse and the rear of the truck.
Does the VEH Stop fuse have power on it with the pedal depressed? Is that fuse good? If yes to both questions, go to the rear of the vehicle and check for power on the light blue wire with the brake pedal depressed.
same issue, no brake lights but i do on the middle light, replaced swicth, have power from the orangs and power to the white when I hit the pedal, still no brake lights
Go to the underhood fuse box and check to see if there is power at the VEH STOP and CHMSL fuses with the brake pedal depressed. Also make sure the fuses are good. If there is no power at those fuses with the brake pedal depressed the problem will be between the stoplight switch and the underhood fuse box. If there is power at the two fuses when the brake pedal is depressed the problem will be between the underhood fuse box and the rear light bulbs.
Does your center high mount stoplight work? Have you checked the bulbs particularly in the CHMSL? What is then year make and model of your truck?
Put all new bulbs in all lights including center mount and none work , its an 01 silverado
I am trying to figure out my problem , I have power from the orange wire to the white wire when I depress the brake pedal meaning the brake sensor is working but I still get no brake lights anywhere