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 assembly
Inspection
1. Inspect coolant
2. Inspect engine oil
3. Inspect battery
4. Inspect air cleaner filter element sub–assy
5. Inspect spark plug
6. Inspect fan and generator v belt
Hint:
you don’t need to check the belt deflection because auto tensioner is adopted.
7. Inspect ignition ti ...
Circuit description
The door key lock and unlock switch is built in the door lock motor.
Wiring diagram
Inspection procedure
1 Check door lock
2 Check wire harness (tvip ecu door lock)
Disconnect the tvip ecu and door lock connectors.
check the continuity between the terminals of the t ...
If the vehicle becomes stuck
Carry out the following procedures
if the tires spin or
the vehicle becomes stuck
in mud, dirt or snow:
Recovering procedure
1. Stop the engine. Set the
parking brake and shift the
shift lever to P.
Do not press the shift release button
after shifting the shift lever to P.
2. Remove the mud, snow ...


