1. Disconnect the negative battery cable..
2. Remove the liftgate upper trim..
3. Remove the rear spoiler..
4. Disconnect the connector.

5. While pressing the high-mount brake light tab in the direction of arrow (1) shown in the figure, press the high-mount brake light in the direction of arrow (2) to detach the high-mount brake light and liftgate.

6. Detach all the high-mount brake light tabs and liftgate and remove the high-mount brake light from the liftgate.

CAUTION:
If the high-mount brake light is removed from the liftgate, the high-mount brake light may fall off and be damaged. When removing the high-mount brake light from the liftgate, hold the high-mount brake light on the lens side with a hand during servicing.
7. Install in the reverse order of removal.
High Mount Brake Light
License Plate LightAir Fuel Ratio (A/F) Sensor Heater Control [Skyactiv G 2.0]
Outline
Based on the control of the A/F sensor heater, a stabilized oxygen concentration
is detected even at low exhaust temperatures, and feedback control of fuel injection
even at cold engine start is made possible for improved cold temperature exhaust
emission performance.
...
Vanity Mirror Illumination Inspection
1. Disconnect the negative battery cable..
2. Remove the sunvisor..
3. Verify that the continuity between the vanity mirror illumination terminals
is as indicated in the table.
If not as indicated in the table, replace the sunvisor.
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Heater Core
Purpose
The heater core heats passing air.
Function
A portion of the engine coolant is taken into the heater core to heat the
air passing through the heater core.
Construction
The heater core consists of a tube which passes engine coolant, and the heat
ra ...