Toyota 2006 Highlander Owner's Manual page 277

Compass sensor
The compass sensor is in the inside
rear view mirror.
NOTICE
Do not put magnets or a metal object
on or near the inside rear view mirror
of the vehicle. Doing this may cause
malfunction of the compass sensor.
'06 HIGHLANDER_U (L/O 0508)
CALIBRATING THE COMPASS (deviation
calibration)
The direction display on the compass
deviates from the true direction deter-
mined by the earth's magnetic field. The
angle of deviation varies according to the
geographic position of the vehicle.
To adjust this deviation, stop the vehicle,
then push and hold the "COMP" switch
until the zone number appears on the dis-
play. Then push the "COMP" switch, refer-
ring to the following map to select the
number of the zone where the vehicle is.
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