My 66 has a brake light "out". My turn signal works, my running light works, and when I press the brake pedal the left brake light functions but the left does not...any clues? Bulb is new, and tested...

 

Dose the left back up light work? If it's out also? Check the ground....

Pull the bulb out and check the green wire for power when the brake is applyed.
If it does the problem is the bulb.... If it has not power, you got a Turn Signal Issue...

Keep us posted on what you find....

 

If you are certain this is the symptom, the problem is right in the turn signal switch.

You can easily check the power going in and out of the switch right at the connector

You can download diagrams and service manuals for free over at MyMopar

 

Hey all thanks for the help. My issue is in my turn signal switch. I messed around with the turn signal switch while parked, and my brake light started working again. I will get into it this weekend, and replace the switch.

 

Did you checked all the connectors for corrosion?