Controller Port A Not Working (Not a Fuse Issue)
Posted: Tue Dec 28, 2021 12:16 pm
Hi Everyone,
I have a spare DC board where Controller Port A doesn't work - the VMU initially beeps but nothing is displayed on it, while controller inputs do nothing. Ports B, C, and D work perfectly.
To rule out the most common issue, I've used a known, working controller board (with a new fuse) + ribbon cable. The controller connector itself is clean with no corrosion, and continuity checks out.
I've swapped the EMI filters between the controller traces to rule those out.
On the underside of the board, the R601 and R602 resistors measure 36 Ohm, while RA602 measures 4.7 kOhm.
The only thing that's really left are pins 5 and 120 of IC201, which I've tried to reflow (albeit with a hot air station since I don't ever work with BGA components) with no success.
Is there anything that can be done to save this board? Thanks!
I have a spare DC board where Controller Port A doesn't work - the VMU initially beeps but nothing is displayed on it, while controller inputs do nothing. Ports B, C, and D work perfectly.
To rule out the most common issue, I've used a known, working controller board (with a new fuse) + ribbon cable. The controller connector itself is clean with no corrosion, and continuity checks out.
I've swapped the EMI filters between the controller traces to rule those out.
On the underside of the board, the R601 and R602 resistors measure 36 Ohm, while RA602 measures 4.7 kOhm.
The only thing that's really left are pins 5 and 120 of IC201, which I've tried to reflow (albeit with a hot air station since I don't ever work with BGA components) with no success.
Is there anything that can be done to save this board? Thanks!