Trouble Code:
P0420 Toyota – Catalyst System Efficiency Below Threshold Bank 1
System:
– Three way catalyst converter Bank 1
– Exhaust tube
– Intake air leaks
– Fuel injectors may be faulty
– Fuel injector leaks
– Spark plugs may be faulty
– Improper ignition timing
– Engine Control Module (ECM)
Notes:
As the code description implies the Toyota P0420 code means that the vehicle’s control module has detected that the three-way catalytic converter is not working properly (is not as efficient as the factory is expecting). Replacing the oxygen (O2) sensors may sometimes fix the code, but in most cases the catalytic convert needs to be replaced to fix the problem. If the Toyota P0420 code is combined with other codes, try fixing the other codes first.
What is the Toyota P0420 code mean?
– Three way catalytic converter Bank 1 does not operate properly.
– Three way catalyst converter Bank 1 does not have enough oxygen storage capacity.
Subsystem:
– Engine Light ON (or Service Engine Soon Warning Light)
Toyota P0420 DTC Description:
The Engine Control Module (ECM) monitors the switching frequency ratio of heated oxygen sensors 1 (front O2 sensor) and heated oxygen sensors 2 (rear O2 sensor).
A three way catalyst converter (Manifold) with high oxygen storage capacity will indicate a low switching frequency of heated oxygen sensor 2. As oxygen storage capacity decreases, the heated oxygen sensor 2 switching frequency will increase.
When the frequency ratio of heated oxygen sensors 1 and 2 approaches a specified limit value, the three way catalyst malfunction is diagnosed.
Applicable For:
2013 Toyota Auris
2012 Toyota Yaris
2012 Toyota Verso-S
2012 Toyota Tacoma
2012 Toyota Prius V
2012 Toyota Prius C
2012 Toyota Prius
2012 Toyota Hilux
2012 Toyota Camry
2012 Toyota Avensis
2012 Toyota Aurion
2012 Toyota 86 GTS
2011 Toyota Tacoma
2011 Toyota Sienna
2011 Toyota Sequoia
2011 Toyota RAV4
2011 Toyota Matrix
2011 Toyota Highlander
2011 Toyota Corolla
2011 Toyota Avalon
2011 Toyota Auris HSD
2010 Toyota iQ3
2010 Toyota Yaris
2010 Toyota Verso
2010 Toyota Tundra
2010 Toyota Prius
2010 Toyota Land Cruiser
2010 Toyota Corolla
2010 Toyota Camry
2010 Toyota Auris
2010 Toyota 4Runner
2009 Toyota iQ
2009 Toyota Yaris
2009 Toyota Venza
2009 Toyota RAV4
2009 Toyota Matrix
2009 Toyota Hilux
2009 Toyota Aygo
2009 Toyota Avensis
2009 Toyota Aurion
2009 Toyota 4Runner
2008 Toyota Sequoia
2007 Toyota Tundra
2007 Toyota Avensis
2006 Toyota RAV4
2006 Toyota Aurion
2005 Toyota Corolla Sedan
2004 Toyota Prius
2004 Toyota Corolla
2003 Toyota RAV4
2003 Toyota Land Cruiser
2003 Toyota Celica