searching ambient temperature sensor

I ran a hardware test on my MacMini 2012 an it gave me the error 4SNS/1/C0000008: TAOP--124. I cannot use the Mac mini anymore because the fan is on full speed and kernel_task is on >300%.

I already know that the error is the Ambient Temperature sensor but i haven't got any hint where it is located. Similar threads on forums are always about MacBooks.

Do you know wether this sensor is on the logic board or is it external? What sensors does the Mac mini 2012 has?

Many thanks in advance