MG Gloster Manual page 94

For vehicles equipped with the heated exterior rearview mirror, press
the Rear Defrost Button to activate the heated exterior rearview
mirror, to help clear the fog or frost on the surface of rearview mirror.
Note: The rear defrost will stop after operating for 15 minutes, and
Its Indicator goes off.
Internal/External Circulation Button
Switch between the internal and external circulation with the button,
when the internal circulation indicator lamp illuminates, it indicates that
it is in internal circulation, when the indicator lamp goes out, it indicates
that it is in external circulation. when it is in the defrost mode, switch to
external circulation forcibly, then you can switch back to internal
circulation manually.
Rear A/C control button
When the ignition switch is in ON position, the REAR button can make
adjustments. Press the button, the indicator lamp illuminates, which
indicates that the front A/C panel can control the rear A/C, at this time,
the adjustments made with the mode, air volume, temperature (left or
right), AUTO, OFF buttons on the front A/C panel are to adjust the
relevant information of rear A/C, if a rear occupant operates the rear
A/C control panel at the time, the signal firstly received in 100ms will be
executed; press the REAR button again, the indicator lamp goes out,
which indicates that the front A/C control panel resumes its control on
the front A/C, and the rear A/C can only be adjusted with the rear A/C
control panel.
86
BEFORE YOU DRIVE
If the REAR indicator is On, after the passenger stops regulating the front
A/C panel for 8 seconds, the indicator automatically goes out, and the
front A/C panel will resume its control on the front A/C.