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:
Repair
1. Steering off center repair procedure
Inspect steering wheel off center.
Apply masking tape on the top center of the steering
wheel and steering column upper cover.
Driving the vehicle on a straight line for 100 meters
at a constant speed of 35 mph (56 km/h), and ho ...
Pre–check
1. Diagnosis check
Starting diagnosis mode (service check mode)
turn off the audio system and turn the ig switch to
acc. While pressing the preset switches ”1” and ”6”
at the same time, press ”cd” 3 times.
Reference:
beep sound is given 3 times and the sys ...
On–vehicle inspection
1. Inspect turn signal flasher relay circuit
Disconnect the connector from the turn signal flasher
relay and inspect the connector on wire harness side as
shown in the chart.
Standard:
Connect the connector to the turn signal flasher and inspect
the wire harness side connector ...


