Hi @philippe71167
Here's the [document|40101] guide, that may help.
Go to Sect 8.4.12 (p.19 of 67 pdf) to view the ''Display'' troubleshooting flowchart.
Use the search function in your browser to find the location of the components mentioned in the flowchart on the boards. You may have to zoom in a lot to find them.
Unfortunately there's no parts list provided with the service manual, so if a component (besides the display assembly) is faulty it may be hard to know its type and value so to be able to get a replacement.