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:
Fuel information
You must only use unleaded gasoline in your vehicle.
Select octane rating 87 (Research Octane Number 91) or higher.
Use of unleaded gasoline with an octane rating lower than 87 may result in engine
knocking. Persistent knocking can lead to engine damage.
At minimum, the gasoline you use should ...
Inspection procedure
1 Check harness and connector(transmission control switch –
body ground)
Disconnect the transmission control switch connector of
shift lever assy.
measure the resistance according to the value(s) in the
table below.
Standard:
2 Inspect transmission control switch
M ...
Inspection procedure
1 Inspect park/neutral position switch assy
Disconnect the park/neutral position switch connector.
measure resistance according to the value(s) in the table
below when the shift lever is moved to each position.
Standard:
2 Check harness and connector(park/neutral position ...