Troubleshooting • HDMI display detected but without output - Pi 4

Up-to-date Bookworm in a Pi 4 4Gb ram
There is a 1080p 7" display that works okay with Pi 3 but there's no output.
I tried some advices I read in other posts like viewtopic.php?t=376631
I removed the SD card and the display shows some features like board, boot, SD, part, fw, net, and tftp but Display.

Accessing via sshConnector 0 (33) HDMI-A-1 (connected)
Connector 1 (42) HDMI-A-2 (disconnected)

HDMI port 0(raindrop:1919): Gtk-WARNING **: 17:13:07.483: cannot open display:

Changing HDMI port and reboot:
HDMI port 1(raindrop:1953): Gtk-WARNING **: 17:37:13.795: cannot open display:

I've tried adding video=HDMI-A-1:1920x1080M@60D to cmdline.txt
Also adding
hdmi_force_hotplug:0=1
hdmi_group:0=1
hdmi_mode:0=4
to config.txt

What else can I try?
Thanks

In my old Buster notes I have data about using tvservice but it does not apply now

Statistics: Posted by marciano — Mon Apr 07, 2025 8:30 pm

---