05-24-2025, 07:23 AM
Quick update. So - after changing backup battery, the problem (errors about LED channels 7 and 8 signal to low) soon returned. Sometimes headlight would work just fine, but mostly not. I continued diagnostics. The HCM turned out to be 100% fine. Voltage levels fine (backup battery solved other glitches). So I just swapped out the headlight. It is likely that the culprit is the the small control module within a headlight assembly itself, but I did not have time to diagnose that.