Toyota Corolla (E120) 2002–2008 Repair Manual / Introduction / How to troubleshoot ecu controlled
systems / Diagnostic trouble code chart
Toyota Corolla (E120): Diagnostic trouble code chart
The inspection procedures are shown in the table below. This table allows efficient and accurate troubleshooting using the diagnostic trouble codes displayed in the diagnostic trouble code chart. Proceed with troubleshooting in accordance with the inspection procedures listed in the diagnostic chart corresponding to the diagnostic trouble codes displayed. The diagnostic trouble code chart for the supplemental restraint system is shown below as an example.

Other materials:
Circuit description
The throttle position sensor is mounted in the throttle body and
detects the throttle valve opening angle.
When the throttle valve is fully closed, a voltage of approximately
0.3 To 1.0 V is applied to terminal vta of the ecm. The voltage
applied to terminal vta of the ecm increases in pro ...
Check mode procedure
Hint:
hand–held tester only:
compared to the normal mode, the check mode has more sensing
ability to detect malfunctions. Furthermore, the same diagnostic
items which are detected in the normal mode can also be
detected in the check mode.
1. Check mode procedure(using the hand–held tester) ...
How to proceed with troubleshooting
The hand–held tester can be used at step 4, 6, 8 and 9.
1 Vehicle brought to workshop
2 Customer problem analysis
3 Warning light check
4 The dtcs check (present and past dtcs)
5 The dtcs chart
6 Circuit inspection
7 Repair
8 Clear the dtcs (present and past dtcs)
9 The dt ...


