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I’ve damaged the display power header pins on the logic board whilst replacing the hard disk drive, snapping one of the pins off (far right pin as you look at the header). This is the header physically on the logic board and not the cable that plugs in to it. Neither is it the display data header/cable. The cable has a black plastic end to it and slots onto 6 metal pins: http://www.macpartsonline.com/922-9849-c… Is it possible to get hold of the relevant header to replace via soldering, or am I resigned to a new logic board? If a new logic board is required can I use any 2011 logic board or is there a specific one for this machine?
Dear Friend, I had the same problem. The connector you need is from Molex. Excatcly the same is not possible to buy, because was made just for Apple LG. I find by Molex the connector has this part number 53780-0670. I purchase it from Mouser electronics under 2€. I think is the same, just not black but white. You can replace it or someone who can fine solder. Yo save a lot of money, believe me! I hope I can help you with this information. Let me know. Bye Bye Update Hello Adam, If I understand the part you me must be this one http://www.digikey.com/product-detail/en… It is a ferrite chip who are responsible for the 12v on LCD Display port. I tok this information from the schematic of Imac 21,5" who has the same connector. I hope this is the part you need. Good Luck! Yako
Adam Smith, I am not Yako, but thought that perhaps I can help you out with the schematic. Here is the L9000 which is a 250ohm ferrite bead used for EMI control as a filter. Check Digikey.com for more info.
Hope this helps, good luck.
Solved! After almost 3 years, due to the fact I was unable to stop and take my Imac for Repair since I work with it to make my incomes. Basically the issue happens because the L9000 Circuit burns if you misconnect the LCD Display cable. I followed all the hints to check the LED Start sequence as you can see on this LCD Backlight not working = solved to this problem. I noticed that LED4 was not blinking on the startup sequence. I connect an external display using Displayport and the Mac was running fine on it. The next step was to buy the circuit from Digi-key, as mentioned by Yako on this post. You can buy the 220 OHM Ferrite Circuit here. Next, I take my iMac to an electronics specialist who confirmed that the Circuit was burned. He welded it again and TADA, LCD working again! SOME TIPS: a) The L9000 Circuit is below the GPU. So you will need to remove the logic board and the GPU (the whole thing with the cooler, etc.) Check the picture below to see where the Circuit is located
b) I Paid something like $10 for 5 220 OMH Ferrite Circuit on Digi-key. Link above.
Here are some pictures after the burned Circuit was removed and the new circuit Welded. c) I paid $200 for the welding service and repair. Thanks, everyone for the tips. Thanks a lot, Yako and everyone here for the tips and help.
I discovered that a blown L9000 is my problem as well on a Mid-2010 iMac 21.5inch. Attached is an image of the blown inductor, for reference to others. You do have to remove the GPU from the slot and peel back the insulating tape to see the damage. One clue for me was you could see the tape was burnt thru, even before peeling it back to reveal the damaged L9000.
