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:
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
...
Circuit description
The vehicle equipped with abs detects a vehicle speed using the stability
control ecu and wheel speed
sensor. This sensor monitors a wheel rotation speed and sends the signal to the
ecu.
The stability control ecu converts these wheel speed signals into a 4–pulse
signal and outputs it to ...
Data list/active test
1. Data list
Hint:
according to the data list displayed by the obd ii scan tool or hand–held
tester, you can read the value
of the switch, sensor, actuator and so on without parts removal. Reading the
data list as the first step of
troubleshooting is one method to shorten labor time.
W ...