Tuesday, December 13, 2011

Dead Dreamcast clock battery No More!

 How many times have you powered up your good ol (10 years to be exact) Dreamcast to be met with this message:

Yup, Your clock battery is dead. and every time you power it on your going to be met with the same "re-enter time" message unless you do something about it. Well, Heres what you'll need:

Philips (+) screwdriver
Soldering Iron
Solder wick
New Lithium ion Battery
Lithium ion Battery cradle (more on this later)

First, Lets get inside this sucker, Flip the dreamcast over and remove the Modem.

Then unscrew the 4 black screws located in each corner and open her up

On the front of the system behind where the controls pug in you'll see a small board with a Litium ion battery mounted on it.
unplug the ribbon cable from the board

Pull the control mount panel up and forward slightly

Pull the board upwards at an angle to remove it from the system.

Here is your control board with the clock battery on it.

Now here's where it gets fun and you get to do some soldering. The Dreamcast came with a surface mounted clock battery thats not replaceable like say, the lithium ion battery on a PC motherboard. we're going to fix this by installing a battery cradle so the battery can be replaced with greater ease in the future (i.e. no soldering).

But first, De-soldering! Use the soldering iron to heat up the solder connections between the board and the battery. Use your solder wick to pull the solder off the battery connections.

Heat the solder on the bottom with the wick in between to get it off the board.
Your going to need a lithium ion Battery Cradle. Notice how the three pins on the mount match the three pins coming out of the original Dreamcast battery

Left to right: Old Dreamcast battery, Battery mount/Cradle, New Battery
New Battery Mount/cradle

Take the Battery mount and stick the three pins into the holes where the old Dreamcast battery was and solder it in. They should plug in with no problem.
New mount on board
Solder into place

Place new battery in mount


 All you need to do from here is reverse the dis-assembly steps so they... assemble. yeah. Anyways PRESTO! Wait...

Oh yeah, You have to enter the Date and time... But this is the last time! Next time you turn it off the System will actually save the time. Now you can play Dreamcast and your system info won't be all over the place.
The Sega Dreamcast makes an excellent system for your porch

The best part about replacing the clock battery with a mount is that if you play your Dreamcast for another 10 years and the battery dies again all you need to do is unscrew those 4 screws and pop in another battery. That's it, you don't even need to remove the board again. Its like replacing the battery of a VMU. To be honest, the clock battery is going to wear out in about 4 or 5 years anyways. Also, I reccomend going to Radio Shack or a pharmacy and buying a name brand battery for $5 or so. When I first did this I bough a large pack of Lithium Ions at the 99 cent store so I could power up my VMUs as well. The Clock battery was dead again in a month. I went out and spent real money on an Energizer battery, popped that one in the system and its been fine for a while now.


  1. Seems that www.iFixit.com has a video on the same subject. Well... I don't care. I used a cradle.

  2. The Dreamcast uses a rechargeable battery. A CR2032 is not rechargeable so the Dreamcast is trying to charge your common battery. Bad news... Use the proper battery or modify the circuit cutting the recharge circuit.

    1. So which battery is the correct one to use then?

    2. An ML2032 will work perfectly for your battery holder. The original battery is an ML2413 but it will work regardless.

    3. Correction: the original batery is an ML2430-VS1


  4. if you want to use NON-rechargable battery you need to mod circuit because can be exposed
    remove resistor (between battery and flat cable) and put 1N4007 diode
    battery side anode
    Flat cable side kathode

    1. I agree with Ayklrl's comment. It's super simply to pull the resistor under the controller board and add a 1N4007 diode. This effectively rejects charging current and makes the voltage flow directional (output from battery to console only.)

      The problem is after 2 years my name brand (Panasonic) CR2032 died, with an expiration of 2024, so I'm thinking Sega used a rechargeable for a reason. Perhaps there is more current draw than a normal RTC circuit? I haven't run any long-term tests yet but there seems to be high demand from the clock battery. I'd install a ML2430-VS1 in the socket but I don't use the console enough to keep it charged (and they have a pretty high parasitic discharge rate and are only 90mah to begin with.)

      Since I've already put a diode in, I'm not going to even consider rechargeable. I'm going to actually install a 2xAA holder and mount it in front of the CD-ROM assembly. I can pickup two high current (3000+ mAH) Energizer AA's, perhaps even those "Lithium Technology" ones that would provide potentially decades of service.