[SOLVED] Black screen on e6420 Sierra upgrade

[someitalian123]

Hi,

 

I recently tried to upgrade my El Captain installation to Sierra after noticing that Jake Lo had updated his guide to include an e6420 bootpack for Sierra. From what I can tell things are working so far except for one major thing. The screen does not work, it’s a black screen and I can only use the laptop via the hdmi out. I do not think this is a bios issue this time, because I saw that the bootpack was for bios version a23, so I updated my bios to a23 beforehand. My monitor’s resolution is 1366x768 and I am using the DSDT-LoRes from the new bootpack, but it would appear that the resolution that is being output, at least via hdmi, is 1360x768, maybe this is the reason why I am getting a black screen? I’ve attached a picture of my tv saying that the resolution is 1360x768, just to show where I got that number from. Any help would be greatly appreciated.

 

 

[Hervé]

Just in case backlight got turned off, try [Fn-Insert] several times. Normally, there is no issue with HD3000 graphics and output to built-in LCD. Did you check the Display PrefPane and the SysProfiler Graphics tab to see if the built-in screen is registered?

[someitalian123]

I tried fn-insert but it made no difference, the backlight is definitely on because the screen is providing visible light, the only problem is that it's black. I checked the display prepane and the sys profiler, both the built-in lcd and my tv are listed. It also appears that I am able to change the output resolution via the display prepane, but the built-in lcd remains black while only the resolution on my tv changes.

[Bronxteck]

what boot loader are you using? if using clover check your congif.plist and nvram for backlight level and remove it. if using chameleon you might have to repatch your framebuffers

[Jake Lo]

Did you use the Config-LoRes.plist rename to Config.plist as well?

[someitalian123]

Yes I did.

[Jake Lo]

Try using the El Capitan Config file and DSDT you were using. We could update the Sierra patches if it works.

You could also try resetting BIOS to default and then SATA Operations to AHCI and see if that helps since you updated the BIOS.

[someitalian123]

I just tried my old El Capitan Config file and DSDT and it worked. Now what do I do?

[Jake Lo]

Can you switch the old Config with my new DSDT and see if that works?

or myConfig and your DSDT and see if that works.

Send me the file whichever works and I'll see what's the difference.

thanks

[someitalian123]

The old config with the new DSDT doesn't work, but the new config with the old DSDT does. So what exactly do you want me to send, the old DSDT? The old DSDT is located here https://osxlatitude.com/index.php?/topic/9131-solved-e6420-monitor-sleep-turn-off-on-boot-fresh-install-of-el-capitan/?p=61321
 
You had patched it for me a couple of months back.
 
Also what am I missing for getting the audio working, it I noticed that audio works via hdmi but not through the on-board speakers. I copied the files in the LE folder to /Library/Extensions and I ran the following script in the terminal. What I'm a doing wrong?

#!/bin/bash

if [ $(id -u) != 0 ]; then
     echo "You need to run this script as root. Type sudo -s, enter password and run this script again."
exit
fi
sudo chmod -Rf 755 /L*/E*
sudo chown -Rf 0:0 /L*/E*
sudo chmod -Rf 755 /S*/L*/E*
sudo chown -Rf 0:0 /S*/L*/E*
sudo touch -f /L*/E*
sudo touch -f /S*/L*/E*
sudo kextcache -Boot -U /
echo "Finished"