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:
Timing gear cover oil seal
Replacement
1. Remove engine under cover rh
2. Remove front wheel rh
3. Remove fan and generator v belt
Turn the v–ribbed belt tensioner slowly clockwise and
loosen it. Then, remove the fan and generator belt v and
put back the v–ribbed belt tensioner little by little and fix
it ...
Circuit description
The vapor pressure sensor and the vsv for the canister closed valve (ccv) are
used to detect abnormalities
in the evaporative emission control system. The ecm decides whether there is an
abnormality in the evaporative
emission control system based on the vapor pressure sensor signal.
Dtc p0 ...
Circuit description
Shifting from 1st to o/d is performed in combination with on and off of the
shift solenoid valve s1 and s2
controlled by ecm. If an open or short circuit occurs in either of the solenoid
valves, the ecm controls the
remaining normal solenoid valve to allow the vehicle to be operated smoothly
...


