This is caused by physical damage, and if you don't have the tools and skills you need, you can't repair it.
Although the kernel log reports a problem with the temperature sensor, this problem is rarely caused by the actual temperature sensor failure. It is usually caused by a bad chip on the hash board. You can detect and replace the defective chip by using a test fixture.
Sometimes, PSU failure may also cause temperature sensor failure. Therefore, it is necessary to test the PSU. First, unplug the other two hash boards for testing. If it is invalid, it is not a PSU-related problem.
Troubleshooting a faulty temperature sensor steps:
Check -ve and +ve leads are correct
Check you are using the correct type of cable
Check for local heat sources affecting your readings
Check the setup of your temperature controller/readout
Resolve out of range errors
Resolve Sensor Break/Open circuit errors
Physically inspect sensor for damage
Check temperature transmitter
Test faulty thermocouple with a multimeter
Test faulty resistance thermometer with a multimeter