Numeric fault codes
MicroBT surfaces every problem as a NUMBERED code (visible in the web UI, WhatsMinerTool, and via the API get_error_code), grouped by subsystem. You decode the number to the subsystem and apply the matching field fix. Golden triage rule: separate CONFIG faults (2000-series) from HARDWARE faults (power/temp/fan/board).
→ Decode the number → act on the indicated subsystem. Config codes need config fixes; hardware codes need reseat/RMA.
200-275 (Power / PSU)
The integrated PSU's fault family. 200 = no power found (CB never saw PSU). 206/250/251/271 = input UNDERvoltage (very common). 233-238 = output over-temp/over-current. 253/254/274 = PSU fan. Hex 0x0001-0x2000 come from the PSU itself.
→ Fix the grid/voltage and cooling first; genuine PSU hardware faults are an internal-PSU replacement (heavier than an Antminer brick swap).
300-360, 600-610 (Temperature)
300/301/302 = SM0/1/2 sensor DETECTION error (check adapter/ribbon wiring). 320-322 = reading error. 350-352 = board over-temp PROTECTION (shutdown). 360 = general overheat. 600/610 = ambient too high.
→ Wiring for sensor codes; cooling/ambient for protection codes.
410-590 (Hashboard / chip)
SMx = the hashboard in slot x (the last digit is the board number, 0-3). 410-412 = SMx detect EEPROM error (can't read the board's ID/EEPROM chip). 420-422 = SMx parser EEPROM error (EEPROM data corrupt). 430-432 = SMx chip-bin type error. 440-442 = SMx EEPROM chip-num error (chip count doesn't match firmware). 450-452 = SMx EEPROM transfer error. 510-512 = SMx wrong hashboard type/version fitted. 520-522 = SMx wrong chip bin/model. 530-532 = SMx not found (board not detected — usually a connection fault). 540-543 = SMx reading chip id error (board detected but its chip IDs can't be read; where a verified model/revision exposes SM3, code 543 refers to that slot; the M56S++ board count remains unverified). 550-552 = SMx has bad chips (dead ASIC chips — swap/RMA). 560-562 = SMx loss of balance (power/hashrate imbalance).
→ Reseat/re-torque/reflash for detect, read, and balance codes; bad-chip codes are a board RMA.
2000-2350 (Pool / network)
The CONFIG/connectivity family - usually not hardware. 2000 = no pool configured. 2010 = ALL pools disabled (check internet/DNS). 2020-2022 = poolN connect failed. 2030 = high rejection rate. 2310-2350 = hashrate too low / loss too high.
→ Fix config/DNS/network for the 2000-series; check voltage/board for the 2300-series.
110-140 (Fan)
The cooling-fan family (air units). 110/111 = fan-in / fan-out detect speed error. 120-131 = fan speed deviation (reads far off the 2000/3000+ RPM target). 140 = fan speed too HIGH - usually the miner ramping fans against a hot intake or an airflow blockage.
→ Reseat or replace the affected fan with the correct part; for 140, fix the airflow/ambient driving it.
5070-5072 (Liquid flow)
Liquid-cooled units only. 5070/5071/5072 = SM0/1/2 water/liquid velocity abnormal - the per-board coolant flow is out of range (too low or none).
→ Restore proper coolant flow (pump, blockages, level, QDs); a true sensor fault is a sensor swap.
