68kMLA Classic Interface
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| Capacitor caught on fire in IIfx | |
| Posted by: campbellashe on 2026-03-17 16:01:46 Okay. I was a bit excited; just got a new (to me) IIfx; was told it booted and chimed. I had some work to I to clean it up, but wanted to ensure the chime myself. I put in the two batteries and plugged in the computer and a monitor. Pressed the power button and got a chime! But this was quickly followed by a snap and flame emanating from the board. It was the tantalum capacitor at C1-- can't read the number on the board as now it is a bit scorched. I quickly unplugged it and alerted my family that things were okay.... just a little fire.... A couple of questions.... a) Is the board screwed now.... b) Is it just the tantalum capacitor -- is it just the cap or something more c) What should my next move be to figure this out... I can replace the cap obviously; but how else to trouble shoot. Thanks for any help... I think from others that this is a known issue in C1; I was overzealous and excited and should have replaced the C1... but just need guidance.   | |
| Posted by: finkmac on 2026-03-17 16:18:58 1) probably not, or not in a way that can't be repaired 2) the tantalum capacitor is underrated for the 12v rail. 3) next move would be to remove the logic board and inspect closely follow the take apart guide here clean and inspect the area. beep out the traces too... I've heard the detonation can blow some of them out. | |
| Posted by: Compgeke on 2026-03-17 18:01:12 Tantalum caps just do that. We're going to see a lot of these posts when the "recapped with tantalum" boards start aging more. | |
| Posted by: campbellashe on 2026-03-17 18:24:41 Fortunately everything seems to trace out okay looking at the BOMARC schematics. Removed the burnt cap; and cleaned up the pads. Ordered a replacement polymer with higher voltage rating. Will update once I get the new caps in.... Any other surprises that I should be aware of for a new IIfx owner... | |
| Posted by: campbellashe on 2026-03-28 15:13:30 The DigiKey capacitor came and replaced the C1 with the polymer 35V cap. Works great. | |
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