Honda 2012 Odyssey Owner's Manual page 190

Synchronized Mode
You can set the temperature synchronously for the driver side, the passenger side
and the rear passenger compartment in synchronized mode.
1. Press the SYNC button.
uThe system will switch to synchronized mode.
2. Adjust the temperature using driver's side temperature control dial.
Press the SYNC button to return to dual mode.
uuClimate Control System
1Synchronized Mode
When the system is in dual mode, the driver side
temperature, the passenger side temperature and the
rear passenger compartment (if it is on) can be set
separately.
* uSynchronized Mode
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