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:
Inspection procedure
1 Check d squib circuit(airbag sensor assy center – horn button
assy)
Disconnect the negative (–) terminal cable from the battery,
and wait at least for 90 seconds.
disconnect the connectors between the airbag sensor
assy center and the horn button assy.
for the oran ...
Circuit description
A thermistor is built in the engine coolant temperature sensor and changes
the resistance value according
to the engine coolant temperature.
The structure of the sensor and connection to the ecm is the same as those of
the intake air temperature
sensor.
Hint:
if the ecm detects the dtc ...
Overhaul
Hint: components:
1. Drain manual transaxle oil (m/t transaxle)
torque: 39.2 Nvm (400 Kgf·cm, 29 ft·lbf)
2. Drain automatic transaxle fluid (a/t transaxle)
torque: 17.5 Nvm (178 Kgf·cm, 13 ft·lbf)
3. Remove front wheel
4. Remove engine under cover lh
5. Remove front axle hub lh nut
...