Thank you everybody, thanks very much for the tips.
It was indeed the 2 resistors that went bad. Replacing them solved the issue, my multimeter now works as brand new!
So, R36 and R37 are 470 ohms resistors, you were right.
I did a quick test by soldering common 1/4W 470ohms resistors I had, to check the values of the DV, AC and Ohmmeter, and all is now displayed correctly. (it was for a quick test, I won't use my multimeter like this!)
Now, I need to find those same resistor fuses, which I don't have as spare. Are those 2W or more (4.5mm in diameter, and 15mm long)? Any difference with common high-power 470ohms resistors?
Bruno