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:
Monitor description
Dtc p0451, p0452 or p0453 is recorded by the ecm when the vapor pressure
sensor malfunctions.
P0451
The ecm senses pressure in the fuel tank using the vapor pressure sensor. The
ecm supplies the sensor
with a regulated 5 v reference–voltage and the sensor returns a signal voltage
betwee ...
Precaution
Caution:
the corolla is equipped with srs, which comprises a driver airbag,
front passenger airbag
and side airbag. Failure to carry out service operations in the correct
sequence could cause
the srs to unexpectedly deploy during servicing, possibly leading to a
serious accident. Fu ...
Circuit description
If the engine coolant temperature (ect) does not reach 75°c (167°f) despite
sufficient warm – up time has
elapsed.
Dtc no
Dtc detection condition
Trouble area
P0128
Condition (a), (b) and (c):
cold start
after engine is warmed up
& ...


