CarJoying RK3188 2 Din Head Unit

Firmware update

  • Obtain the latest firmware from the Joying blog at
  • Extract the mcu.img and update.img files to an empty (but formatted) microSD card.
  • Eject the GPS microSD card and insert the microSD card containing the firmware.
  • Reset the unit using the small reset hole at the bottom left.
  • As the unit reboots, push and hold down the volume knob for at least 8 seconds.
  • Once the firmware update screen is displayed, rotate the volume knob to highlight the "update and clear" option - hold the volume button in to select that option.
  • Keep the power connected to the unit (or your car ignition on) until it's finished the update process and rebooted into Android.

Jeep Commander install

Lots of stuff needs to be done to install a 2 Din head unit in a Jeep Commander with the stock radio:

  • reworked the dash by removing the stock factory insert panel, modifying that panel by reducing the height of the top pocket, enlarging the radio hole to 2 Din size and filling the Micky-Mouse ears, then covering the whole thing in some fake carbon fiber vinyl that matches the texture of the factory gear shift surround;
  • fitting the microphone into the overhead compartment, replacing the factory Jeep bluetooth microphone.  I tried to use the factory microphone with the head unit, but it didn't work.  I was able to use the factory microphone enclosure (with some modification) to fit the replacement microphone.
  • fitting the gps antenna at a position forward on the windscreen;
  • installing the reverse camera - reverse signal obtained from white/green stripe wire in harness in passenger footwell (left hand side).

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