ByteRot :: Dreamcast CMOS Battery Replacement

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Dreamcast CMOS Battery Replacement

Device	Sega Dreamcast
Difficulty	Moderate
Time	10 - 30 minutes
Steps	9

This guide is by Dark Sakul on iFixit and is licensed under Creative Commons Attribution-NonCommercial-ShareAlike 3.0. ByteRot mirrors it for non-commercial preservation: formatting changed and photos resized for old browsers; full-size photos and the text are on the FTP in /DOCS/REPAIR. Original guide >>

When a Dreamcast ask for time and date every time you power on your system, your CMOS battery is dead. This guide shows how to replace the CMOS battery.

Please note this guide is outdated and I am going to be updating this guide.

Tools: Phillips #2 Screwdriver; Soldering Workstation; Safety Glasses; Digital Multimeter

Parts: Vertical CR2025 Coin Cell Battery Holder; ML2032 Rechargeable Battery

Step 1

• Locate and remove all four black 12mm Phillips #02 screws from the underside of the console.
• NOTE: Note: Remove the expansion bay to locate the fourth screw

Step 2

• CAUTION: Internal components can be loose. Be careful that they do not fall out when removing the cover.
• Turn the console right side up.
• Remove the top cover by gently lifting the upper portion of the console.

Step 3

• CAUTION: Be gentle with the white controller cable as it can be a bit fragile.
• Disconnect the white controller cable by gently pulling the the cable while wiggling it back and forth until it detaches from the controller board.

Step 4

• Remove the four 14mm Philips #02 screws located on the controller board.

Step 5

• Disconnect the white fan header from the controller port.

Step 6

• Remove the controller board by lifting it up from the controller port.

Step 7

• Note where the positive and negative terminals go.
• Desolder the old CMOS battery from the controller board.

Step 8

• Solder the replacement battery holder to two electrical wires.
• Solder the opposite ends of the wires to the controller board. Make sure to match corresponding points on the board with where the previous positive and negative terminals were.

Step 9

• Reinsert the controller board.
• Attach the battery holder inside with a self adhesive substance, such as double sided foam tape.
• Insert the battery into the battery holder.
• Reverse the disassembly directions to reassemble your Dreamcast.
• Once your Dreamcast is reassembled, go ahead and connect the Dreamcast to your TV or monitor and power, and reset the clock.

Conclusion

To reassemble your device, follow these instructions in reverse order.

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