More Fun Fixing it returns with Part 3 of their Silver Label C64 Fix series. It begins with a KU14194HB board showing no video output at all. This machine offers plenty of mystery, so the repair starts with patience and curiosity. As the testing progresses, the Silver Label C64 fix becomes far more involved than expected.
Inspecting the Board
The case and keyboard look clean, yet several capacitors show clear leakage. Corrosion surrounds the VIC-II area, along with damage near the 74LS629 oscillator. Because these faults can disrupt video and timing, the Silver Label C64 fix focuses on this region first. Soon, broken traces appear under multiple capacitors, hinting at deeper trouble.
Repair Steps in Action
The repairer removes all socketed chips for safety. Next, corrosion is cleaned with a fiberglass pen and fresh solder. Damaged traces get patched with enameled wire, and every point is checked with a multimeter. As each step finishes, the board looks more stable. With new capacitors installed, the board finally powers on and delivers video.
Unexpected Diagnostic Faults
Once video returns, the diagnostics uncover new problems. The serial port and user port both fail the test suite. Swapping CIAs shows no improvement. Since the keyboard and controllers behave correctly, the cause stays hidden. At this point, the Silver Label C64 fix moves from local testing to community support.
Community Insight Leads to Breakthrough
Members of the Retro Hardware Discord offer fresh ideas. User “Hawk” suggests testing the CPU under full diagnostic load. The repairer realizes the original CPU only received a brief power-on test. A known-good replacement is installed, and the diagnostic faults vanish instantly. The Silver Label C64 fix now has a confirmed culprit: a failing CPU that masked itself behind unrelated errors.
Full Restoration and Final Verification
With the CPU replaced and every capacitor renewed, the machine passes all diagnostics. The keyboard works perfectly, the video output looks clean, and the serial port responds without issue. The repairer considers inspecting the RF modulator later, yet for now the machine feels strong and ready for use.
Closing Thoughts
This repair highlights steady troubleshooting and the value of community knowledge. Hidden failures can create misleading symptoms, and this case makes that clear. The video walks through each step, from corrosion cleanup to the final boot screen, offering helpful detail for anyone restoring vintage hardware.
Watch the full episode to see how the Silver Label C64 fix brings another classic Commodore back to life with careful testing and a bit of teamwork.
