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:
How to proceed with troubleshooting
The hand–held tester can be used at step 3, 4, 6, 9.
1 Vehicle brought to workshop
2 Customer problem analysis
3 Connect the obd ii scan tool or hand–held tester to dlc3
4 Check and clear dtc and freeze frame data
5 Visual inspection
6 Setting the check mode diagnosis
7 Proble ...
Circuit description
This circuit turns on the magnetic clutch inside the actuator during cruise
control operation according to the
signal from the ecu. If a malfunction occurs in the actuator or speed sensor,
etc. During cruise control operation,
the rotor shaft between the motor and control plate is released.
...
Source voltage drop
The srs is equipped with a voltage–increase circuit (dc–dc converter) in the
airbag sensor assy center
in case the source voltage drops.
When the battery voltage drops, the voltage–increase circuit (dc–dc converter)
functions to increase the
voltage of the srs to normal voltage.
...


