Toyota Corolla (E120) 2002–2008 Repair Manual / Diagnostics / Sfi system / Catalyst system efficiency below
threshold
Toyota Corolla (E120): Catalyst system efficiency below threshold
Dtc p0420 catalyst system efficiency below threshold (bank 1)
Other materials:
Washer fluid
Add washer fluid in the following situations:
● A washer does not work.
● Vehicles without a multi-information display: The low windshield washer fluid
warning light (if equipped) comes on.
● Vehicles with a multi-information display: The warning message (if equipped) appear ...
Symptom confirmation and diagnostic trouble code
Hint:
the diagnostic system in corolla has various functions. The first
function is the diagnostic trouble
code (dtc) check, in which a malfunction in the signal circuits to the ecu
is stored in code form in
the ecu memory. Another function is the input signal check, which checks if
...
Do-it-yourself service precautions
If you perform maintenance
by yourself, be sure to follow
the correct procedure
as given in these sections.
Maintenance
WARNING
The engine compartment contains
many mechanisms and fluids that
may move suddenly, become hot,
or become electrically energized.
To avoid death or serious injury,
obser ...


