Since this harness unavailable, you'll have to determine where the disconnect is to the one class light. I can't tell exactly how they're wired from that small picture, but if they're in series or parallel, you could replace the 2mm ceramic LED. If they're separately powered, you may have to test the LED's first to see if one is defective. If they're good, trace back to see where the disconnect is. My guess is poor solder or a contact issue in the harnesses. It looks like a pretty convoluted wiring scheme, there are multiple wiring harnesses between the lights and the RCMC main board.