W202_NY

planning upgrading the 3rd brake light, by removing it completely, and installing one similar to a current C300 type. there is currently 1 wire that's connected to a pcboard, that has 2 wires, can I assume that these 2 wires are +/-. and that all I need to is cut the connector off and then connect to my new led light. I have removed the compete assembly, and dont see any other wires, unless they are hidden underneath the rear shelf, which I plan on lifting and making sure that these are the 2 main wires I need to use......any confirmation or other info I should be aware of ?