Waterpik Aquarius WP-660 water flosser

The Waterpik Aquarius WP-660 suddenly stopped working, the main fuse tripped, and further it did not respond to button presses, the LED doesn't turn on any more.

Diagnostics

 * Plug in the device, and confirm that pressing the button does not turn on the motor and the LED. Power consumption is 0.
 * Open the bottom case by unscrewing the 5 (long) bottom screws. They are inside the black feet.


 * There's a single PCB, which connects to the pump motor and to the 12VDC power supply (red/black wires).


 * Plug in the device and check the 12VDC output of the power supply (measure on the PCB). If no voltage is generated, the power supply is faulty.

Unfortunately I couldn't find a replacement for the power supply (part number xkd-p1500ic12.0-18W), but this is a 12V 1.5A supply and we can replace it with a power adapter.

Replacing the power supply
We can use an external power adapter which can provide 12VDC and at least 1.5A. You can find them at the local hardware store, or use one from an old device, they are very common.


 * Waterpik Aquarius WP-660 with wires replaced.jpg the power supply cord, close to the old power supply. Strip the white shield (4-5cm) and the wire ends. The long (stiff) wires should allow some flexibility, as the device vibrates a lot and it can stress the solder joints.
 * De-solder the old black/red wires, and replace them with the wire cord (blue/brown). Pay attention to the polarity, use the same one at the other end.
 * Cut the power plug, and replace it with a DC barrel jack (as pictured), or connect directly to the power adapter wires.
 * Test, and afterwards put everything back together. Pay attention to the cable seals, as this device can be operate in humid environments.