Toyota Corolla (E120) 2002–2008 Repair Manual / Diagnostics / Combination meter / How to proceed with troubleshooting
Toyota Corolla (E120): 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

Other materials:
Dtc check/clear
1. Dtc check (normal mode)
Notice:
hand–held tester only:
when the diagnostic system is switched from the normal
mode to the check mode, all the dtcs and freeze frame
data recorded in the normal mode will be erased. So before
switching modes, always check the dtcs and freeze frame
data, and ...
If your vehicle needs to be towed
If towing is necessary, we
recommend having your
vehicle towed by your Toyota
dealer or commercial
towing service, using a
wheel-lift type truck or flatbed
truck.
Use a safety chain system
for all towing, and abide by
all state/provincial and local
laws.
WARNING
Observe the following precautions.
...
Circuit description
The variable valve timing (vvt) system includes the ecm, the oil control
valve (ocv) and the vvt controller.
The ecm sends a target ”duty–cycle” control signal to the ocv. This control
signal, applied to the ocv,
regulates the oil pressure supplied to the vvt controller. Camshaft timin ...


