My 5200's recently developed a problem. Regardless of where I turn the iron heater knob, the display shows the iron temp warm up to 480C every time. The iron is hot and works, but I need the ability to adjust the temp. Any ideas? A schematic of the iron section would help. Thank you.
Turned out to be a bad pot. Wiper was somehow shorted to one of the other pins. Swapped it with the other 5k pot for the air temp and it works fine. 480C is evidently the max temp and should've been a clue. I'll post a link to a replacement part once I've found it and have verified that it fits. Hope this helps someone.