According to the Antminer Z15 kernel log, two cooling fans are not found; you can troubleshoot by the following methods.
Troubleshooting:
1. Check whether the fan cable and extension cable is plugged in properly or have poor contact. If there is, it is recommended to re-plug;
2. Replace the two cooling fans not detected in the log.
Click the article below to learn more!
>>How to correctly troubleshoot the problem of the miner's fan?