I’ve got a difficult one... (I joined the forum simply to ask this question so I’m hoping you all can help me!)
I have a 2017 5k iMac 580 8gb 3.8 i5 with 2Tb Fusion Drive that I upgraded.
I put in a 4Tb Samsung 870 SSD, a 2Tb Samsung nvme and a 4.2ghz i7
After installation, everything worked as expected except I inserted the card a bit too far and seemed to have damaged the LCD a little bit as there were vertical lines across a portion of the screen that wasn’t working. I purchased a new display and used the iMac for 2 weeks Until it arrived, using the previous display without any issue.
\/\/\/\/\/\/\/\/ And This is where the problems happened. (Instantly) \/\/\/\/\/\/\/\/
1. My (brand new) display came in. (Nothing with hardware has been touched)
2. I unplugged the 2 display cables while the iMac was on. (I know this was stupid.)
3. I look at the back of the new display and noticed it didn’t have the LVDS cable. I removed the LVDS cable. (At this point I hear the iMac’s fans ramping up to 100% which up to this point had not happened before. (neither Display is connected yet)
4. I attach the LVDS cable to the new display and plug the new display in. It doesn’t turn on. (Fans still at 100%)
5. I turn off the computer, unplug it. Turn it back on, reset the PRAM, still doesn’t work. Remove the screen and test out the old display to determine if the new replacement LCD is non-functional.
Old LCD all of a sudden is not displaying an image either. Fans still at 100%.
The diagnostic LEDs on the motherboard shows 3 LED’s strong at 100% brightness. The 4th LED i am 100% sure is on but I’m also 100% sure it’s about half the brightness as the other LEDs.
I researched to see what the issue could be.
I plugged in an external monitor and the external monitor worked without an issue.
I found out that the display had a temperature sensor and assumed the LVDS wasn’t transmitting the video signal and therefore must also not of been transmitting the temp sensor signal, and figured that I must have broken the LVDS cable Which is why the fans were at 100% (default for not getting an LCD signal) and also why there was no video, so I purchased a new LVDS cable.
7. After installing a NEW LVDS cable the image didn’t display on either LCD with either cable. I very carefully transferred the LCD temp sensor to the new Display and that still didn’t seem to subdue the fan speed.
8. I’m completely at a loss at what could be the issue. I’m a little hesitant to mess with something that I knew worked and haven’t touched other than remove the display.
to summarize:
The fans are on At 100%
2 displays are not producing video. (One that worked but was damaged, and the other brand new.)
Diagnostic Motherboard LED #4 is dim But definitely on. Other 3 are bright.
External (secondary monitor is working).
2 LVDS cables are not transmitting video signal to the main display. (That or power or something) idk...
The Start Chime is working fine.
Any suggestions on what to look for, how to fix or anything else to consider? Thanks!
I have a 2017 5k iMac 580 8gb 3.8 i5 with 2Tb Fusion Drive that I upgraded.
I put in a 4Tb Samsung 870 SSD, a 2Tb Samsung nvme and a 4.2ghz i7
After installation, everything worked as expected except I inserted the card a bit too far and seemed to have damaged the LCD a little bit as there were vertical lines across a portion of the screen that wasn’t working. I purchased a new display and used the iMac for 2 weeks Until it arrived, using the previous display without any issue.
\/\/\/\/\/\/\/\/ And This is where the problems happened. (Instantly) \/\/\/\/\/\/\/\/
1. My (brand new) display came in. (Nothing with hardware has been touched)
2. I unplugged the 2 display cables while the iMac was on. (I know this was stupid.)
3. I look at the back of the new display and noticed it didn’t have the LVDS cable. I removed the LVDS cable. (At this point I hear the iMac’s fans ramping up to 100% which up to this point had not happened before. (neither Display is connected yet)
4. I attach the LVDS cable to the new display and plug the new display in. It doesn’t turn on. (Fans still at 100%)
5. I turn off the computer, unplug it. Turn it back on, reset the PRAM, still doesn’t work. Remove the screen and test out the old display to determine if the new replacement LCD is non-functional.
Old LCD all of a sudden is not displaying an image either. Fans still at 100%.
The diagnostic LEDs on the motherboard shows 3 LED’s strong at 100% brightness. The 4th LED i am 100% sure is on but I’m also 100% sure it’s about half the brightness as the other LEDs.
I researched to see what the issue could be.
I plugged in an external monitor and the external monitor worked without an issue.
I found out that the display had a temperature sensor and assumed the LVDS wasn’t transmitting the video signal and therefore must also not of been transmitting the temp sensor signal, and figured that I must have broken the LVDS cable Which is why the fans were at 100% (default for not getting an LCD signal) and also why there was no video, so I purchased a new LVDS cable.
7. After installing a NEW LVDS cable the image didn’t display on either LCD with either cable. I very carefully transferred the LCD temp sensor to the new Display and that still didn’t seem to subdue the fan speed.
8. I’m completely at a loss at what could be the issue. I’m a little hesitant to mess with something that I knew worked and haven’t touched other than remove the display.
to summarize:
The fans are on At 100%
2 displays are not producing video. (One that worked but was damaged, and the other brand new.)
Diagnostic Motherboard LED #4 is dim But definitely on. Other 3 are bright.
External (secondary monitor is working).
2 LVDS cables are not transmitting video signal to the main display. (That or power or something) idk...
The Start Chime is working fine.
Any suggestions on what to look for, how to fix or anything else to consider? Thanks!
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