CRT tv displays RGB in black and white

[Hathaer1]

Hi,

I have an issue with my Samsung UW-21J10VD displaying a black and white picture when I connect a scart cable from my SNES. The cable is from the multi AV port at the back of the snes and is supposed to send an RGB signal with Sync over Luma. The scart port on the TV is marked as RGB. I have tested the set up on another more modern TV and it displays colour. I also tried the same cable and CRT tv with another SNES and found it still displays a black and white picture. I have tried to read up on this issue and I suspected it might be to do with the Blanking signal so tested that on the cable, with the SNES on and found it was 5v.
Could the tv need less than 3 volts for this or is anything between 1v and 5v OK?
Is there any way for me to manually put 5v on the circuit board to test if this is working or even test if there's 5v going to the right place?

I downloaded the wiring diagrams, but I couldn't understand where the scart input would be to try and follow where it would go.

Thanks for any help.

[Tak-MK]

When you change AV port using the TV controller, check that it's using RGB and not just composite over scart. Some TVs actually say RGB instead of AV1 for example. That would mean that your TV was actually using composite over scart and doesn't get the color frequency well if it's from another region (either the TV or the SNES).
As far as I can see here (https://www.manua.ls/samsung/uw21j10vd/manual?p=77), your TV supports RGB.

[Hathaer1]

I don't have a remote control for the TV. I'm just using the menu buttons for now but I have ordered a second hand one that should arrive tomorrow.

I would have thought selecting the RGB SCART av port as the input on the TV would have been enough but hopefully it works with the controller.

Thanks.