Toyota Corolla (E120): Circuit description
The door courtesy switch turns on when the door is opened and off when the door is closed.
Wiring diagram

Other materials:
Location
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If a warning light turns on or a
warning buzzer sounds
Calmly perform the following actions if any of the warning
lights comes on or flashes. If a light comes on or flashes, but
then goes off, this does not necessarily indicate a malfunction
in the system. However, if this continues to occur, have the
vehicle inspected by your Toyota dealer.
Actions to ...
Pressing power switch does not start system
Wiring diagram
Inspection procedure
1 Inspect radio receiver assy(+b, acc, gnd)
Check that the continuity between terminals at each
condition, as shown in the chart.
Standard:
Check that the voltage between terminals at each condition,
as shown in the chart.
Standard:
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