E4406A风扇控制板产生连续噪音

嗨，我在“E4406A风扇控制板”上遇到了一个问题。
风扇保持全速而不会减速，产生连续噪音非常烦人。
我已经尝试使用另一台工作良好的另一台仪器的控制板（E4406-60044），并将有缺陷的仪器恢复工作。
问题出在“A14风扇控制板E4406-60044”上。
你可以让接线图能够修复吗？
非常感谢。
debugasm



     以下为原文

  Hi,

I have one problem on "E4406A Fan Control Board". The fan remain at full speed without ever slowing down, creating a continuous noise very annoying.  

I've tried using an other the control board (E4406-60044) of another instrument that works well and the defective one back to work.

The problem is on "A14 Fan Control Board E4406-60044".

You can have the wiring diagram to be able to repair it ?

Thanks very much.

debugasm