Tektronix TDS3012 main board failure loading down the PS

[snoopy]

I was using my TDS3012 today when the screen when all white and then I turned it off and I cannot get it to power back on again !

To cut a long story short the power supply is ok and I have gone through all of the troubleshooting guide in the S/M and it has led me to the main board being faulty.

When you switch it on you see the fan momentarily move and sometimes a bit of light on the LCD screen but there is obviously something shorted out on the main board which is dragging the whole power supply down.

Anyone fixed these at the board level ?

cheers
david