P0420 prius 2006. In the first picture i was coasting which shuts the engine off then i hit the throttle momentarily then coasted again. P0420 toyota description the engine control module monitors the switching frequency ratio of heated oxygen sensors 1 front o2 sensor and heated oxygen sensors 2 rear o2 sensora three way catalyst converter manifold with high oxygen storage capacity will indicate a low switching frequency of heated oxygen sensor 2. Exhaust leak if theres a noticeable exhaust leak coming from the vehicle it can change what the o2 sensors register enough to throw the p0420 code.
P0420 2006 toyota prius description the engine control module monitors the switching frequency ratio of heated oxygen sensors 1 front o2 sensor and heated oxygen sensors 2 rear o2 sensora three way catalyst converter manifold with high oxygen storage capacity will indicate a low switching frequency of heated oxygen sensor 2. P0420 2008 toyota prius description the engine control module monitors the switching frequency ratio of heated oxygen sensors 1 front o2 sensor and heated oxygen sensors 2 rear o2 sensora three way catalyst converter manifold with high oxygen storage capacity will indicate a low switching frequency of heated oxygen sensor 2. This is where the powertrain code p0420 comes in to play.
The way that toyota prius ensures that it is staying economically friendly is to monitor the catalyst and set a trouble code should it fail. Prius timing if your prius is misfiring or the exhaust timing is off this can affect the gasses that are actually going to the o2 sensors enough to cause the p0420 code to register. My 2005 prius is throwing a p0420 code catalytic converter.
The ecu determines the efficiency of the catalytic converter cat using two sensors. You should always properly repair your emissions related equipment this is for informational purposes only. I just got a scan tool that works on my phone and got the two plots below.
The p0420 code is stored in memory when the ecu detects a low efficiency in the catalyst system for bank number 1 the bank of cylinders where cylinder number 1 is located.
P0420 Catalytic Converter System Bank 1 Efficiency Below Threshold Troublecodes Net
www.troublecodes.net