When the interior light switch is in the DOOR position and all doors (and tailgate) are locked and closed, the room lamp will come on for 30 seconds if any of the below is performed.
At this time, if you press the door lock button, the lamps will turn off immediately.
Kia Cee'd JD Service Manual: Repair procedures
Inspection
Signal Circuit Inspection
1.
Check clutch switch pull-up voltage
(1)
IG KEY "OFF", ENGINE "OFF".
(2)
Disconnect clutch switch connector.
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Kia Cee'd JD Owners Manual: Rear window defroster
■ Manual climate control
■ Automatic climate control
The defroster heats the window to
remove frost, fog and thin ice from the
interior and exterior of the rear window,
while engine is running.
To activate the rear window defroster,
press the rear window defroster button
lo ...