Toyota Corolla (E120): Circuit description
This is the power source of the ecu, hence the actuators.

Wiring diagram

Other materials:
How to proceed with troubleshooting
1 Vehicle brought to workshop
2 Customer problem analysis
3 Problem symptom confirmation
4 Circuit inspection
5 Repair or replace
6 Confirmation test
7 End
Customer problem analysis check
...
On–vehicle inspection
1. Inspect drive belt
Visually check the belt for excessive wear, frayed cords,
etc.
If any defect is found, replace the drive belt.
Hint:
cracks on the rib side of a belt are considered acceptable. If the
missing chunks from the ribs are found on the belt, it should be
replaced.
2 ...
Check and replace ecu
Notice:
start an inspection of the connector from the backside
of the connector on the wire harness side with
the connector connected to the ecu.
When no measurement condition is specified, perform
the inspection with the engine stopped and also
the ignition switch on.
First check the ec ...


