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:
Circuit description
The o/d main switch (transmission control switch) is a momentary type switch.
When pressing the o/d main
switch, the o/d off indicator light lights up and the ecm prohibits shifting
into o/d, and when pressing it
once again, the o/d off indicator light goes off and the ecm allows shifting
in ...
Circuit description
The throttle position sensor is mounted in the throttle body and
detects the throttle valve opening angle.
When the throttle valve is fully closed, a voltage of approximately
0.3 To 1.0 V is applied to terminal vta of the ecm. The voltage
applied to terminal vta of the ecm increases in pro ...
Outside vehicle
General maintenance
Performing these maintenance checks on the vehicle in the owner’s
responsibility. The owner may
perform the maintenance or take the vehicle to a service center.
Check the parts of the vehicle described below on a daily basis. In most cases,
special tool are not
requir ...