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:
Circuit description
The intake air temperature (iat) sensor, mounted on the mass
air flow (maf) sensor, monitors the intake air temperature. The
iat sensor has a thermistor that varies its resistance depending
on the temperature of the intake air. When the air temperature
is low, the resistance in the thermisto ...
Circuit description
The purpose of this circuit is to prevent the engine from stalling while
driving in lock–up condition, when
brakes are suddenly applied.
When the brake pedal is depressed, this switch sends a signals to the ecm. Then
the ecm cancels the operation
of the lock–up clutch while braking is i ...
Inspection procedure
1 Check voltage at ig2 of airbag sensor assy center
Disconnect the negative (–) terminal cable from the battery,
and wait at least for 90 seconds.
disconnect the connector of the airbag sensor assy center.
connect the negative (–) terminal cable to the battery,
and wa ...


