This is a long shot, but I'll throw it out here in hopes that there may be some battery nerds here who could help, so that I don't have to go join another forum. I'm all kinds of nerd, but batteries/electronics is very much not my thing.
I bought a set of K2 rechargeable CR123 batteries and the matching charger in hopes that I'd have a rechargeable solution for my Surefire EDCL1-T, which is my EDC and nightstand light. It covers both task and "tactical" roles for me. Rechargeables would be great, because I wouldn't have to play the guessing game as to when my batteries are worn down enough by tasks that I need to replace them to ensure emergency reliability.
I went with the K2s because my understanding is that they were previously sold with Surefire branding as a rechargeable option for multiple Surefire lights, including the EDCL1-T. However, on trying mine, I have the issue that I've seen reported regarding other brands of rechargeable 123s - my light will run with them on low, but high mode won't engage. High mode currently works as usual with a normal CR123.
Is there any "fix" for this, or something obvious I'm missing? Or was there a running change to Surefire's wiring that makes the light incompatible with these cells? Light was purchased in April of 2019. Thanks in advance for any advice, even if it's just "go register on a flashlight forum."