It's only 4.7 ohms and greyed out so I believe it's a fusible resistor. If you can't find a fusible, then you can try flameproof resistors but you'll lose fuse protection. I presume you mean it's completely open (infinity). Anyhow, if you want to confirm that's the issue, you can replace it with another regular resistor or just a jumper and confirm FM is fixed.docs said:With R164 out of the board I can not get any reading out of it at all.