[Philips, Sony, TCL Android TV] ihama:
Hi, my Philips displays the logo and nothing else besides the LED blinking about twice a second. I have tried numerous things and I cannot make it work, but I feel somewhat close. Do you know how to fix it?

The facts: the outside sticker says it's a 55PFL6158K/12, however, the mainboard and the remote were replaced some time ago.

I have been able to go into recovery mode where it says this (see the photo):

PHILIPS/QM16XE_F/QM16XE_F
7.1.2/N2G48H/01610224
user/test-keys
Any button cycles highlight.
Long-press activates.
------
Reboot system now
Apply update from SD card
Wipe cache partition

Now for the speculation: I think (based on what I read in @Toengel 's site and a local technical shop for Phillips that they probably did the "Fusion kit" upgrade when they repaired the board (based on looking at the remote with the Netflix button).

I talked with Phillips and got first the NVM.bin file and later the FUS_QM164E_16.102.24_prod.zip file as well as the upgrade_loader.pkg, upon really insisting that it was probably not the original model board and it was the 55PFL6158S/R1 with a QM16.4 chassis.

Things that I have tried:

I tried the autoupgrade for the original model (went to recovery with a single line mount error displayed, IIRC)

All the above files for the 55PFL6158S/R1

None of the upgrade_loader.pkg are seemingly recognized at all (from Phillips or Toengel's), even a downgrade to QM164E_0.16.56.3_upgrade_loader.zip I got from @Toengel's site does not seem to be picked up for installation.

With the autorun.upg files (specially the one) there is some indication that the TV notices them but the only indication is that the logo disappears and eventually

I tried wiping the cache partition and that appeared to work without errors when I tried it. I attach a recovery.log file that one of them produced, in case it helps (it has lots of details)

I tried to connect via USB and adb says there are no devices connected. I tried the USB3 connector and it charges my laptop but does not seem to connect for data

The USB2 connectors are also not responding to adb

I tried connecting it via ethernet and my DHCP server does not register any request for IP

Because the WiFi was for a different location, it's not connecting here and I am not sure how to change it. I heard here that it's possible to connect adb via network, but only on WiFi, is that correct?

I tried various wipedatatool.upg (or some with .zip) for models that looked close, but I never found a wipedatatool for the model of the baseboard. Is there one for this baseboard? I asked Phillips support but they are so so hard to crack and they always say no no no (until I press for more, since my other option is to trash the tv).

When I put two USB sticks in at the same time in the USB2 ports, I can see one in the "apply update from SD card" however, nothing works when attempted from there, although maybe I was not exhaustive with that.

I have been able to boot to recovery from pressing with DOWN button on the back of the screen, but only once and never again. Any ideas as to how to do this reliably?

I think I tried more things perhaps, but I did not take notes, so maybe I forgot.

I used to do some Android dev and I am technical. However, I am not sure if I can get any "pacakge" to reinstall the system or clean it up. Or even see console logs through adb or something.

Any advice on how to save this system and TV will be appreciated!! Thanks in advance!!

Update: I opened the back and saw a sticker on the board that says 42PFL6008S/R1 which confirms the suspicion it is an /R1 upgrade. Photo attached. However, since it appears that has the same firmware, it does not change things much, perhaps?