Description
OBD-II Trouble Code Description for P0420 Honda
Catalyst System Efficiency Below Threshold
What does this mean?
OBD2 Code P0420 Honda definition:
The catalytic converter has an oxygen sensor in front and behind it. When the vehicle is warm and running in closed loop mode, the upstream oxygen sensor waveform reading should fluctuate. The downstream O2 sensor reading should be fairly steady. Typically the P0420 Honda code triggers the Check Engine Light if the readings of the two sensors are similar. This is indicative of (among other things) a converter that is not working as efficiently as it should be (according to specs). It is part of the vehicle emissions system.
Symptoms
Possible sumptoms of OBD code P0420 Honda
You will likely not notice any drivability problems, although there may be symptoms.
Causes
Possible causes of OBD code P0420 Honda
A code P0420 Honda may mean that one or more of the following has happened: Leaded fuel was used where unleaded was called for An oxygen sensor is not reading (functioning) properly The engine coolant temperature sensor is not working properly Damaged or leaking exhaust manifold / catalytic converter / exhaust pipe Retarded spark timing The oxygen sensors in front and behind the converter are reporting too similar of readings
Possible Solutions
Some suggested steps for troubleshooting a P0420 Honda error code include: Check for exhaust leaks at the manifold, pipes, catalytic converter. Repair as required. Use a scope to diagnose the oxygen sensor operation (Tip: The oxygen sensor in front of the catalytic converter normally has a fluctuating waveform. The waveform of the sensor behind the converter should be more steady). Inspect the downstream heated oxygen sensor (HO2), replace if necessary Replace the catalytic converter One thing to note is that many vehicle manufacturers offer a longer warranty on emissions-related parts. So if you have a newer car but it’s out of it’s bumper-to-bumper warranty, there still may be warranty on this type of problem. Many manufacturers give a five year, unlimited mileage warranty on these items. It’s worth checking into. See also: P0420 Honda.com – P0420 Honda Help
The OBD2 Code Information Be Applicable For Honda:
2013 Honda Urban SUV Concept,2013 Honda S660 Concept new,2013 Honda NSX-GT Concept,2013 Honda N-One,2013 Honda GEAR Concept,2013 Honda Civic,2013 Honda CR-Z,2012 Honda Civic,2011 Honda Jazz,2011 Honda Accord,2010 Honda Insight,2010 Honda CR-V,2009 Honda City,2008 Honda S2000,2008 Honda Accord,2007 Honda Fit,2007 Honda Civic,2007 Honda CR-V,2007 Honda Accord,2006 Honda Civic,2005 Honda Element,2005 Honda CRV SE,2005 Honda CRV EX,2003 Honda Element,2003 Honda CR-V,2002 Honda NSX,2002 Honda Civic Si,2002 Honda Accord SE,2001 Honda NSXR Concept,2001 Honda Model X Concept,2001 Honda Civic Si Concept,2001 Honda Civic Concept,2001 Honda CR-V,2001 Honda Accord Sedan,2001 Honda Accord Coupe,2000 Honda S2000,2000 Honda Passport,2000 Honda Insight
Note:
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