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:
Circuit description
Refer to dtc p0120
Dtc no.
Dtc detection condition
Trouble area
P0121
The following condition is met 4 times. After the vehicle speed
has exceeded 19 mph (30 km/h) once, the throttle position
sensor output value is out of normal range when the throttle
...
Circuit description
When the ignition switch is turned on, battery positive voltage is applied to
the coilwhich closes the contacts
of the efi main relay (marked: efi) and supplies power to terminal +b of the ecm.
This signal causes current to flow to the coil, closing the contacts of the efi
relay and supplyin ...
On–vehicle inspection
1. Check fuel pump operation
Connect the hand–held tester to the dlc3.
turn the ignition switch on and hand–held tester main
switch on.
Notice:
do not start the engine.
select the active test mode on the hand–held tester.
please refer to the hand–held te ...


