In my previous post where I mentioned I had the same problem and it turned out to be the valve stem I should have said it was the valve itself. Make sure you submerge the entire valve stem.
Did you spray the soapy water on the valve stem too? I had a very slow leak that took a couple of weeks before I saw the tire was low. It turned out to be a very very slow leak from the valve stem.
What about these?
https://www.amazon.com/s?k=Self+Adhesive+Mounts+Set+for+Wire+Management+with+Stick+Pads+Anchors+Clips&i=tools&crid=R9630MFLQWET&sprefix=self+adhesive+mounts+set+for+wire+management+with+stick+pads+anchors+clips+%2Ctools%2C184&ref=nb_sb_noss
"the navigation screen suddenly went black" this sounds like a power issue.
"“weak signal.” this sounds like an antenna issue. Is there an option to see the number of and strength of the received satellite signals. Do you have voltage going to the antenna?
Try one of these. I installed one years ago and like it. Just listen for a change in the pitch of the whistle, it gives you a second or two to stop pumping gas.
https://www.westmarine.com/attwood-fuel-vent-line-surge-protector-303851.html
I once had a boat that had the fuel tank mounted in the rear of the boat. I had to lower the bow at the gas station to be able to fill the tank completely. If I didn't the pump would shut off 5 or 6 gallons short of actually being full.
What looks like a diode next to it may be fried too? The only way to confirm is to remove it and check with an ohm meter. If you're going to mess with the resistor remove it, maybe the under side of it isn't too burnt to read the color bands.
I use several pieces of PVC to hold my cover up and never had an issue with the heat affecting the PVC, my cover is dark brown. Where do you live and how hot does it get?
I agree with both above. It's unlikely the manufacturer will help you dig in to the gauge to fix it and there's a reason the resistor burnt. Save your time and hassle trying to fix it and just replace it.