Left headlight LED channel 7 and 8 error - blinker fails

[volver]

So I had to do a whole lot of learning and experimenting to just find out that for some reason the weak backup battery, which is located under the hood of Volvo S60 2019, was causing the weird errors in HCML about LED channels 7 and 8. Interestingly no other direct or indirect errors were seemingly caused by it, and HCMR was error-free.
Orbit Support was very helpful to me by explaining the inner workings of HCMs, and even providing updated software for those.
So thanks to everyone!