Toyota Corolla (E120): Circuit description
The key unlock warning switch comes on when the ignition key is inserted in the key cylinder and goes off when the ignition key is removed.
Wiring diagram

Other materials:
On–vehicle inspection
Notice:
”cold” and ”hot” in these sentences express the temperature of the coils
themselves. ”Cold” is from
–10 c (14 f) to 50 c (122 f) and ”hot” is from 50 c (122 f) to 100 c (212 f).
1. Inspect ignition coil (with igniter) and spark test
confirm dtc.
Notice:
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Inspection procedure
1 Check connector
Disconnect the negative (–) terminal cable from the battery, and wait at
least for 90 seconds.
check the connection of the combination meter connector and the
airbag sensor assy center connectors.
Ok:
the connectors are connected.
2 Check combination ...
Circuit description
The seat belt buckle switch (lh) circuit consists of the airbag sensor assy
center and front seat inner belt
assy (lh).
Dtc b0126/b0127/27 is recorded when a malfunction is detected in the seat belt
buckle switch (lh) circuit.
Wiring diagram
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