MPC3500 sc670

[dara]

[jonhiker]

SC670 :No response from controller at power on
When the main power is turned on or the machine starts warming up
from energy-saving mode, the controller does not receive a command
signal from the controller.
 Loose connection
 Defective controller
 Defective controller board
1. Check the connection between the BCU and controller.
2. Replace the controller.
3. Replace the BCU.

When you replaced the NVRAM and then downloaded the data back onto the new NVRAM, you could have reloaded any corrupt files from the old NVRAM. You now may have 2 bad NVRAMs.