HDMI/ DVI inputs failed approx. one month after connection of Denon home theater receiver with HDMI pass-through feature "on." Gear successfully re-connected via component video inputs. Self-diagnosed via unit Service Manual as Main Board failure; diagnosis confirmed verbally by local TV tech. Replaced Main Board successfully, but this did not restore HDMI/ DVI inputs. Removed replacement Main Board and re-installed original Main Board. Now, upon initial plug-in, power supply relay clicks & green power LED lights. After approx. 2 sec., power supply relay clicks again, green power LED turns off, OPC LED flashes red at one-second invervals indefinitely. Have not performed further diagnosis other than making sure everything was reconnected following re-installation of original Main Board. Perhaps I missed something on the LED control unit (or broke a conductor in the ribbon connector between LV sockets on LED control unit and Main Board)?

Thank you for the prompt reply. I apologize for not having included my model number:
Sharp LC-37GB5U (we LOVE this unit!)
Correct: new problem is that it will not power-on. Following reinstallation of the original Main Board and seeing red OPC, I swapped the Main Boards again. This new power-on problem is now experienced with either Main Board installed.
I will re-check all of my connections within the next couple of days and report back to you. I probably need a replacement AV Board, but won't know for sure until I re-establish power to the unit..
Thanks again!
Mike Thank you for the prompt reply. I apologize for not having included my model number: Sharp LC-37GB5U (we LOVE this unit!) Correct: new problem is that it will not power-on. Following reinstallation of the original Main Board and seeing red OPC, I swapped the Main Boards again. This new power-on problem is now experienced with either Main Board installed. I will re-check all of my connections within the next couple of days and report back to you. I probably need a replacement AV Board, but won't know for sure until I re-establish power to the unit.. Thanks again! Mike

Digital inputs on AV unit had failed; replaced with used unit ($75 on eBay).

As far as the blinking red OPC light after my initial repair attempt, I discovered that I had accidentally peeled back some of the silver contacts on the FD, LV, and FC connecting cords (ribbon cables) when I plugged them back into their respective sockets. I was able to obtain replacement FD and LC cables from www.partstore.com; unfortunately cable FC was sold-out, but I was able to repair the original, and everything is working normally once again.

WORD OF CAUTION TO FELLOW AQUS OWNERS: If any of your newer home theater or BD/ DVD components has a feature to automatically turn itself on or off by sensing a digital signal from your TV, make sure these features are OFF!!! The two silver face Sharp Aquos models we have (both 1080i max.) do NOT have HDMI-control capability. I believe I damaged our Aquos' digital input by turning this feature of our new receiver ON.

I no longer run any HDMI signals through the receiver to the TV: DVR goes directly to TV's HDMI input, BD player goes directly to TV's DVI input. Only running audio signals through the receiver now (optical from DVR; coaxial from BD player). Works great! Digital inputs on AV unit had failed; replaced with used unit ($75 on eBay). As far as the blinking red OPC light after my initial repair attempt, I discovered that I had accidentally peeled back some of the silver contacts on the FD, LV, and FC connecting cords (ribbon cables) when I plugged them back into their respective sockets. I was able to obtain replacement FD and LC cables from www.partstore.com; unfortunately cable FC was sold-out, but I was able to repair the original, and everything is working normally once again. WORD OF CAUTION TO FELLOW AQUS OWNERS: If any of your newer home theater or BD/ DVD components has a feature to automatically turn itself on or off by sensing a digital signal from your TV, make sure these features are OFF!!! The two silver face Sharp Aquos models we have (both 1080i max.) do NOT have HDMI-control capability. I believe I damaged our Aquos' digital input by turning this feature of our new receiver ON. I no longer run any HDMI signals through the receiver to the TV: DVR goes directly to TV's HDMI input, BD player goes directly to TV's DVI input. Only running audio signals through the receiver now (optical from DVR; coaxial from BD player). Works great!