Toyota Corolla (E120) 2002–2008 Repair Manual / Introduction / How to troubleshoot ecu controlled
systems
Toyota Corolla (E120): How to troubleshoot ecu controlled systems
- General information
- How to proceed with troubleshooting
- Customer problem analysis
- Symptom confirmation and diagnostic trouble code
- Symptom simulation
- Diagnostic trouble code chart
- Problem symptoms table
- Circuit inspection
- Electronic circuit inspection procedure
Other materials:
Check short circuit
If the wire harness is ground shorted as shown in fig. 5,
Locate the section by conducting a resistance check with
the body ground in step (b).
Check the resistance with the body ground.
Disconnect connectors a and c and measure the
resistance between terminals 1 and 2 ...
Gauges and meters (multi-information display)
The displayed content may differ depending on the type of meter.
1 Tachometer
Displays the engine speed in revolutions per minute.
2 Speedometer
3 Fuel gauge
4 Multi-information display
The multi-information display presents the driver with a variety of drivingrelated
data including the cu ...
Circuit description
When the ignition switch is turned on, battery positive voltage is applied to
the coilwhich closes the contacts
of the efi main relay (marked: efi) and supplies power to terminal +b of the ecm.
This signal causes current to flow to the coil, closing the contacts of the efi
relay and supplyin ...


