"Maintenance Mode" message does not appear on the MID, as it doesn't apply to the XL40 Siennas.
In a nutshell:
-Press power button 2 times
-Step on accelerator 2 times
-Shift to Neutral
-Step on accelerator 2 times
-Shift to Park
-Step on accelerator 2 times
-Observe CDY-2E message on MID
-Step on brake, press power button, to turn on vehicle as normal
-To terminate, turn off vehicle as normal