PowerMac G4 MDD

The G4 MDD is the third and final generation of Apple's Power Mac G4s, named so due to its Mirrored Drive Doors. It was produced from 2002 to 2004, and is notable for being one of the last Macs capable of running Mac OS 9 (with some caveats).

Causes

 * Power Supply is Faulty with bad capacitors.
 * When you try to power up your MDD, you will typically get a quick power light and fan spin and it will shut off.

Solutions

 * Recapping the entire power supply generally fixes the problem. Although there is a chance some other components are faulty.

Disassembly Notes
Please be careful when opening the power supply because there are high voltage capacitors inside which can cause great injury to yourself. There are 5 screws holding the housing together and 4 screws holding the fans that need to be removed. Once the screws are removed, the top part of the housing needs to slide away from the fans. After that disconnect the fan cables. There are 4 screws holding the board in place, one in each corner. The board can then slide out of place and you will need to flip the board over and desolder the two power cables (blue and brown, please take a picture of where these are located before desoldering them to help with reassembly). After that the board should be completely free.

ACBel API1PC36
''This recapping guide is only for the ACBEL 360w and 400w API1PC36 Rev. B power supply units. There are Samsung power supplies also for the MDD which this guide does not cover.''

ACBel API1PC36
''If parts are not available or different selection is preferred, you can use the values in the Original Parts section to perform a parametric search. Replacement capacitors can be found on both digikey and mouser, or pick your preferred source.''

Related Links

 * https://www.badcaps.net/forum/showthread.php?t=83705&highlight=mac+g4&page=3