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:
Refueling
Opening the fuel tank cap
Perform the following steps
to open the fuel tank cap:
Before refueling the vehicle
Turn the engine switch off and
ensure that all the doors and
windows are closed.
Confirm the type of fuel.
■Fuel tank opening for unleaded
gasoline
To help prevent incorrect fueling, ...
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
When driving uphill under cruise control, in order to reduce the number of
shifting due to on–off overdrive
operation and to provide smooth driving, when down shifting in the
electronically controlled transmission occurs,
a signal to prevent upshift until the end of the uphill slope is sent ...