Why 2006 dodge ram 2500 the brake light will not work checked all fuses all are fine the right brake light works but the left doesn't checked to see if the power comes to the back but it doesn't?

Open Circuits

From what I understand of your problem, IF the fuse for that circuit IS good, then the problem is probably that the wiring of that circuit issuffering from what is called an "open,"[disconnected] conditiion somewhere in that part of the circuit which serves only the nonworking light.

For an electrical circuit to function, the circuit must be "" which" means that a conductor [wire] must be attached to the Positive terminal of the battery and run [through various harnesses and connectors, plugs, etc.] to the fuse, then to a control switch [not needed in this case of yours], then to the electrical device (in this case your "outlets"), and then another wire [called a ground] back to the Negative terminal of the battery. Sometimes the ground wire does not go all the way back to the battery Negative terminal, but instead connects to the body sheet metal near the device, and the body sheet metal is all grounded to the Negative terminal of the battery.

This continuous line of electrical conduction makes a "circuit." IF any part of that circuit is disconnected at a connector, or a screw terminal, or at a sheet metal ground screw, the circuit is "open," incomplete, and cannot conduct the electricity.

The "fix" for your problem is for someone who understands and is experienced in automotive electrical systems to fully "troubleshoot" that electrical circuit to find and identify the defect and then to properly correct it.

Although there could be one of many possible defects, you need to find it, and fix it in order to cause the circuit to work as it should.

Another thing that comes to mind is that often fuses will "look OK" yet be incapable of conducting electricity. How do you know that:

• You even found the correct fuse to determine that it is "not burned out?" If you checked and confirmed good the wrong fuse that was an exercise in futility. And...
• Even if it was the right fuse, how did you determine that it was "not burned out?" A visual check may not indicate a burned out fuse. You need to test it with a VOM [Volt-Ohm meter] to confirm that there is conductivity.

You will probably find a loose or corroded metal contacts in a connector or light socket, or a burned out filament in the bulb, or a cut wire in the light circuit which is nonfunctional.