A guide to diagnosing and repairing common DSi faults
My DSi doesn't turn on!?
This is one of the most common DSi fualts. The bad news is it can have many different causes. The good news is that with a little bit of knowledge you can often diagnose the offending component without even opening your beloved DSi. Other times you may need to grab a screwdriver, use some logical reasoning and possibly a little educated guessing to complete a differential diagnosis.
Reason 1) - A blown fuse
DSi's have 2 fuses, one on the motherboard and one on the D-Pad Powerboard. The most common fuse to blow is the fuse on the D-Pad Power Board. This is good news because replacing a D-Pad Power board is easy and cheap. When a fuse is blown the DSi will not respond at all when the power button is pressed. No lights will flash or turn on, there will be no sound, and none of the screens will flash. If a fuse is blown the DSi will be totally unresponsive, dead! If when you press the power button one of the lights turns on or flashes, one of the screens flash, or if there is any sound the offending component is not a blown fuse (see below for further diagnosis). When a DSi fuse is blown the amber charge light will often still turn on when charger is plugged in.
If your DSi fault fits the above description for a blown fuse then we recommend replacing the DSi D-Pad Power Board.
Reason 2) - LCD screen connection error
If an LCD screen is not connected to the motherboard correctly the DSi will turn on very briefly and then turn off. The screen with the poor connection will not turn on at all, the screen that is connected propeller will flash white very briefly (if neither of the screens are connected properly neither of the screens will flash). For example if there is a problem with the top screen LCD screen ribbon cable connection the DSi will turn on very briefly whilst the bottom LCD screen flashes white and the top LCD screen will not do anything. Their are 2 common causes of LCD connection errors:
a) the DS has sustained damage to the left hinge and the top screen ribbon cable which runs through the left hinge has sustained damaged. If this has happened to your DSi then you will need a new top LCD and new case. If you do not repair the case ASAP you run the risk of also damaging the camera ribbon cable which also runs through the lift hinge.
b) whilst repairing the DSi an LCD screen ribbon cable was not connected properly. If this is happening to your DSi and you have just attempted a repair, go back and unclip the LCD ribbon cables, and make sure you push the ribbon cables firmly into the ribbon cable clips before clipping them down again.
Note that a poorly connected touch screen will still allow the DS to turn on correctly, although the touch screen will not respond.
Reason 3) - Damaged or unplugged DSi wireless module
If a DSi's wireless module is damaged or unplugged from the motherboard the DSi's blue power light will turn on and stay on when the power button is pressed. If this is happening to your DSi then you need a new DSi wireless module.
Reason 4) - Damaged camera ribbon cable
The DSi's camera ribbon cbale runs thouIf the DSi camera ribbon cable is damaged the DSi will not respond at all when the power button is pressed, the amber / orange light will turn in when the charger is plugged in
DSi differential diagnosis tips
Use these repair tips to help diagnose what component is broken in your DSi
If you connect only the motherboard and power board only together, then attach the battery and press the power bottun, the blue power light will turn on and stay on if the power board and motherboard are intact. Use this trick to confirm or rule out that the faulty component is on either the power board or the motherboard. If the blue light does not turn on, most commonly it means the fuse on the power board is blown and you need a new DSI power board.
If the top LCD ribbon cable is damaged or not connected properly the blue power light will turn on briefly and the bottom LCD screen will flash on very briefly when the power button is pressed.
If the bottom thin LCD ribbon cable is damaged or not connected properly the blue power light will turn on briefly and the top LCD screen will flash on very briefly when the power button is pressed.
If the DSi's wireless module is damaged or not connected properly the DSi's blue power light will turn on and stay on whilst the top and bottom LCD screens stay black when the power button is pressed.
If the DSi camera module cable is damaged the DSi will not respond at all when the power button is pressed, the amber / orange light will turn in when the charger is plugged in.
If you connect the battery backwards you will blow the fuse on the power board.
