Contacting customer support (via the support button at the top of the page, or email@example.com) should narrow down the cause pretty quickly. The machine’s logs should reveal why the light is yellow.
I realize this may not be your problem but for anyone else following this thread I just had that yellow light for my first time and it was the white ribbon cable that completely unplugged itself while the machine was attempting a set focus operation. I honestly never had that thing disconnect and I have never taken it off even for the limited cleaning I do. I put it on when I received the machine and up until yesterday never touched it. Then for some bizarre reason the head moved left and the ribbon disconnected which resulted in a failure and a yellow light. Easy fix for me although I am scratching my head as to why it suddenly parted ways.
Check if the ribbon cable is sticky at all. At one point mine had gotten sticky enough that it started sticking to itself at times, and this caused the print head to get stuck at one point, and pulled the end of the cable loose as well. If not sticky, it might’ve just vibrated itself out of the connector over a very long time.
I’ve got no suggestion as I’ve never had this issue, but if you want to post your logs (or DM to me) I’ll take a look to see if I can identify the issue. There are some clear errors generated for certain conditions.