Toyota Corolla (E120) 2002–2008 Repair Manual / Introduction / How to troubleshoot ecu controlled
systems / Problem symptoms table
Toyota Corolla (E120): Problem symptoms table
The suspected circuits or parts for each problem symptom are shown in the table below. Use this table to troubleshoot the problem when a normal code is displayed in the diagnostic trouble code chart but the problem is still occurring. Numbers in the table indicate the order in which the circuits or parts should be checked.
Hint: when the problem is not detected by the diagnostic system even though the problem symptom is present, it may be that the problem is occurring outside the detection range of the diagnostic system.

Other materials:
Engine immobilizer system
The vehicle’s keys have built-in transponder chips that prevent the engine
from starting if a key has not been previously registered in the vehicle’s on-board
computer.
Never leave the keys inside the vehicle when you leave the vehicle.
Vehicles without a smart key system: The indicator li ...
Inspection procedure
1 Check tvip ecu
Check that the operation of the tvip function is normal.
Hint:
with this inspection, the tvip ecu cpu can be diagnosed if it works normally or
not.
2 Check wire harness (tvip ecu integration relay)
Disconnect the tvip ecu and integration relay connectors.
ch ...
Precaution
1. Notices when checking
power door lock/unlock function:
the wireless remote control function operates only when the following 3
conditions are met.
No key is inserted into the ignition key cylinder.
All the doors are closed. However, doors can be unlocked even wh ...


