Sega Dreamcast controller port repair

*Note*
This write-up is provided for informational purposes ONLY! I cannot guarantee anything in regard to what is stated below. By opening your Dreamcast you effectively cancel any warranty you may have (if any). Since it involves electronics use common sense and caution, if you are not sure, don't do it! Thanks!
*End Note*

A common occurance in the Dreamcast world is the "Blown Controller Port" syndrome. Usually third party controllers bring this about via their greater tendency to have shorts in their wiring, thus overloading the fuseable resistor on the controller port PCB.
To repair this is very easy and takes minimal soldering experience. The fuseable resistor rating will vary depending on the production generation and location of manufacturing. I've personally seen:
4.7 Ohm 1/4 Watt 5% Tolerance
and
3.9 Ohm 1/4 Watt 5% Tolerance
for the Fuseable resistor in question ( Labelled F1 on the Controller Port PCB).
So the exact "range" that that circuit can handle is unknown, but the most common practice is either to get an exact replacement (kinda hard to track down those particular stats) or run two 10 Ohm 1/4 Watt 5% Tolerance fuseable resistors in parallel which will effectively make it a 5 Ohm 1/4 Watt 5% Tolerance.

Editor's note: Actually the two resistors considered together will be rated at 1/2 Watt.

"But 5 Ohm is more than the factory had installed!" you may be saying to yourself... this setup has been used sucessfully by many, many people over the last few years. The main thing is that you stick with fuseable resistors, if you use a standard carbon resistor and it blows again, those run the possibility of catching fire, which in general is not a good thing.

Simply open your Dreamcast, remove the top portion of the case and you will see the controller port PCB, the fuseable resistor you need to replace is just off center towards the back of the board (labelled F1), remove blown resistor as neatly as possible and then replace. As with any soldering, don't leave excessive heat on the PCB or the resistor, do it as cleanly and quickly as you can. Also it's a good idea to test it with a multimeter before you close the whole thing up again.

Also of note, when you remove the top section of the Dreamcast case, the power supply will be on the upper left side, as with any power supply, use care with handling / touching any of the components there as some may still have some charge left in them, and you'll get a zap! Better safe than sorry...

That's about all there is to it! I've done this 3 times and all 3 consoles have been running flawlessly since! Naturally you'll want to try and determine WHICH controller caused your port to blow, and don't use that controller again! (Unless you're up for trying to fix that too!) Good Luck!

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