The Macintosh IIcx has a row of six surface mount electrolytic capacitors near the startup circuit at the bottom left of the board (as per the orientation below). As a result, a Mac IIcx with capacitor leakage will often result in a computer that won’t startup at all. If you have a Mac IIcx and it hasn’t been recapped, you must get it done before it’s too late.
UPDATE: Please be aware that the original version of this guide was incorrect; the two 10µf 16V caps were placed with the wrong polarity. The screen printing on the logic board indicates that these caps should have positive to the right, but the original caps have positive to the left. The original placement of the caps is correct (as is the guide below).
- 10µf 16V KEMET tantalum capacitors (T491C106K016AT)
- 47µf 16V KEMET tantalum capacitors (T491D476K016AT)
- 220µf 16V Vishay axial capacitors (MAL213825221E3)
- 470µf 16V Vishay axial capacitors (MAL211835471E3)