I was not able to load any app from the xmb so I thought that my bd drive was broken. I am not able to open my ps3 as I don't have tools for it and cnt go outside coz of lockdown so trying to do it on software basis
It could be also the connection in between the main motherboard... and... the big chip soldered into the big circuit board inside the BD drive
That chip is the BD controller, and the main motherboard tryes to communicate with it when booting a game/app, and also at a intermediate point of the firmware installations
When that communications fails = black screen
But most of the times is caused because there is a problem in the ribbon cables or the connectors in between the BD drive and the main motherboard
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But you opened the PS3 before ?. And since that point the apps and games was loading into a black screen ?
If both thing happened at the same time (the black screens inmedaitly after opening the PS3), it means you forgot to connect one of the ribbon cables... or you did not connected it properlly
That connectors have a clip that moves (you need to use your finger nails to move it), and the clip allows to move to 2 different positions... lets say one is "open", and the other is "closed", there is some people that breaks that clip when trying to disconnect the ribbon cable, in this case it can be fixed with a plastic, take a read at this posts
https://www.psx-place.com/threads/i-need-help-for-broken-blu-ray-ps3.28905/page-2#post-238019
And there is other poeple that pulls from the ribbon cable and disconnects it when the clip is "closed" (but the clip doesnt breaks)... and after that they tryes to insert the ribbon cable with the clip in "closed" position, but is so hard that they doesnt inserts it completly in the connector (and this creates an intermitent electrical connection)
This is even easyer to fix