Toyota Corolla (E120) 2002–2008 Repair Manual / Introduction / How to troubleshoot ecu controlled
systems / How to proceed with troubleshooting
Toyota Corolla (E120): How to proceed with troubleshooting
Hint
: carry out troubleshooting in accordance with the procedures on the following page. Here, only the basic procedures are shown. Details are provided in the diagnostics section, showing the most effective methods for each circuit. Confirm the troubleshooting procedures first for the relevant circuit before beginning troubleshooting of that circuit.
1 Vehicle brought to workshop
2 Customer problem analysis
- ask the customer about the conditions and environment when the problem occurred.
- Check the battery positive voltage.
Voltage: 11 – 14 v (engine stopped)
- visually check the wire harness, connectors and fuses for open and short, etc.
- warm up the engine to the normal operating temperature.
- confirm the problem symptoms and conditions, and check for dtcs according to the related chart.
Ok go to step 5
4 Dtc chart
- Check the results obtained in step 3, then confirm the inspection procedures for the system or the part which should be checked using the dtc chart.
Go to step 6
5 Problem symptoms chart
- Check the results obtained in step 3, then confirm the inspection procedures for the system or the part which should be checked using the problem symptoms table.
6 Circuit inspection or parts inspection
- Confirm the circuit for the system or the part which should be checked using the problem symptoms table or the results obtained in step 4.
7 Repair
- Repair the affected system or part in accordance with the instructions in step 6.
8 Confirmation test
- After completing repairs, confirm that the problem has been solved (if the problem does not recur, perform a confirmation test under the same conditions and in the same environment as when it occurred for the first time).
End
Other materials:
Inspection procedure
1 Inspect transmission wire(s2)
Disconnect the transmission wire connector from the
transaxle.
measure the resistance according to the value(s) in the
table below.
Standard:
2 Check harness and connector(transmission wire – ecm)
Connect the transmission connec ...
Tire pressure warning system (if equipped)
Your vehicle is equipped with a tire pressure warning system that uses tire pressure
warning valves and transmitters to detect low tire inflation pressure before serious
problems arise.
◆ Installing tire pressure warning valves and transmitters
When replacing tires or wheels, tire press ...
Rear view monitor system
The rear view monitor system assists the driver by displaying guide lines
and an image of the view behind the vehicle while backing up, for example while
parking.
The screen illustrations used in this text are intended as examples, and may
differ from the image that is actually displayed on t ...