Hello.
I bought tek TDS420A with all LED on.
I was thinking it'll easy repair but...

At first startup I smell caps. In PS i found 1 bad cap and replaced it. I check all other and looks O.K.
So PS running and all voltages are good.
Then I check 27K smd resistor on CPU board for reset and it is o.k.
On led diplay on cpu board it stops at "-" so cpu clearly running.
It is time to build console adapter and here is the problem:
Bootrom Header Checksum passed.
Bootrom Total Checksum passed.
BootRom Check Sum passed.
Bus Error Timeout test passed.
Bus Error Write to Bootrom passed.
GPIB Test passed.
Kernel Diagnostics Complete.
Calling SDM (monitor) Routine.
SDM (monitor) not enabled.
Enabling Bus Control register. Value = 0x2
Flashrom Programming Voltage is OFF.
Flashrom DSACK and JumpCode test passed.
Invalid Flashrom Body checksum = 0x9115, should be 0x9105
Flashrom Checksum test failed.
Cannot transfer control to Flashrom.
Transferring control to the SDM (monitor).
Can someone help with this.
I suppose firmware is corrupted, but I can't find firmware on google.
So if someone have firmware files and tell me how to flash this scope I'll be very glad.

Sebastijan.