Tektronix MDO4104B-6 soft buttons not working.

[algavauser]

I am trying to fix a Tektronix MDO4104B-6 oscilloscope. The main problem is that the soft buttons in the front panel are not working. A new firmware was installed after the problems and that did not fix it. The oscilloscope does turn on when plugged to the AC. Also, the fan does not spin when turned on(even thought the source is providing the 12V and 5V to the main board), and test points all work except for the +1.5V test point. There was communication from the oscilloscope using the command app on my colleagues laptop. The front panel does light up , yet none of the buttons work (even the "on" button). Is there a way I can start tackling the problem? Thanks.