いたかめ さん、まだそのDTC:の事例など収録してないので T/Bさせて頂ます。


ziziさんも関心を示す、排ガスの値で 以前からCO2も一部加えたものを別な視点で記録してますが
そこにも触媒の反応を反映しているのかと思えるケースも稀にみかけます。 一部のファクターで


 さて、診断器の対応が いたかめ さんも指摘されてますが、同じような逆輸入車で似たケースが
あり、HDM3Kではなく違う機種で対応した。 手元の古いTO:国産資料でもDTC:にP0420の項目が無い。






P0420 - Catalyst System Efficiency Below Threshold (Bank 1)

2010/7/11(日) 午後 0:52ogw*og*2返信する



A P0420 code is a trouble code on OBD-II equipped vehicles. All vehicles from 1996-newer sold in North America support this generic powertrain code. This code is a pretty common one and this site is here to help the average do-it-yourself (DIY) car owner (like you) troubleshoot, diagnose, and fix their vehicle themselves when presented with a P0420 code, saving money.

2010/7/11(日) 午後 0:53ogw*og*2返信する



If your car has multiple trouble codes (DTC's), it's always a good idea to fix them in the order they come up on the code reader. For example, if you have these codes - P0300, P0420, P0171, then you're going to want to tackle the P0300 Random Misfire code first (resolve it), and then tackle the P0420 code, etc. The reason for that is that the first code could be causing further DTCs to be set.

2010/7/11(日) 午後 0:53ogw*og*2返信する



Common Problems That Trigger the P0420 Code
Inefficient Catalytic Converter(s)
Defective Front or Rear Oxygen Sensor(s)
Misfiring engines

2010/7/11(日) 午後 0:57ogw*og*2返信する



Common Misdiagnoses
Oxygen Sensors

Polluting Gases Expelled
HCs (Hydrocarbons): Unburned droplets of raw fuel that smell, affect breathing, and contribute to smog
CO (Carbon Monoxide): Partially burned fuel that is an odorless and deadly poisonous gas
NOX (Oxides of Nitrogen): One of the two ingredients that, when exposed to sunlight, cause smog

2010/7/11(日) 午後 0:58ogw*og*2返信する



How does a P0420 code trigger the check engine light? This code will trigger the check engine light as follows:
1996-newer (OBD-II) vehicles use oxygen sensors and a catalytic converter to reduce emissions. There is one O2 (oxygen) sensor in front of the catalytic converter (called upstream), and one behind it (downstream).

2010/7/11(日) 午後 2:27ogw*og*2返信する



When the engine is warmed up and running normally the upstream oxygen sensor reading fluctuates and the downstream one is fairly steady. In the case where both readings are fairly steady, a P0420 check engine light code is set.
Possible Causes: 

Oxygen (O2) sensor not working correctly
Damaged or leaking exhuast (pipe, manifold, catalytic converter)
Damaged catalytic converter
Diagnostic Help:

2010/7/11(日) 午後 2:29ogw*og*2返信する



To diagnose a P0420 trouble code we begin by checking for exhaust leaks under the vehicle. Then use an oscilliscope to check the waveforms of both upstream and downstream O2 sensors. The front reading should vary, the rear should be steady. Replace as necessary. Check the rear Heated O2 Sensor.

2010/7/11(日) 午後 2:31ogw*og*2返信する



The catalytic converter is probably the most important emission control device on a vehicle because it cleans up the pollutants in the exhaust. Thanks to fuel injection, oxygen sensors in the exhaust manifolds, and a feedback fuel control system, emissions are kept to a minimum. Even so, some pollution is still produced and must be eliminated by the converter.

2010/7/11(日) 午後 2:35ogw*og*2返信する



So the converter must be in good condition and working correctly to keep tailpipe emissions to an absolute minimum. And if there’s a problem? Then your customer’s vehicle will probably need a new converter.

Converter problems typically fall into one of five categories:

1. Plugged converter (partially or completely);

2. Dead converter;

3. Marginal converter (still working, but efficiency is down);

4. Damaged converter (rust or physical damage); or

5. Missing converter (somebody

2010/7/11(日) 午後 2:36ogw*og*2返信する



ziziさん、NOxも測定できているのですね。 燃焼後の

2010/7/11(日) 午後 3:47

2010/7/11(日) 午後 3:54ogw*og*2返信する



After a run on motorway my trc, vsc and engine management lights came on.

Local independent garage got 3 error codes: c1203, c1201 and p0420.

he reset everything and said it was probably just some sensor, but took car on motorway run and same lights came on again. Can anyone shed some light, dont think the guy at the garage was that clued up on toyotas as he mainly deals with vauxhalls and dont want to take it to dealers.

Or does anyone know of a good independent mechanic in bolton a削除

2015/10/4(日) 午前 2:13ogw*og*3 ]返信する




DTC:P0420: The O2 sensors are looking at all this activity, and are sending data to the PCM continually. The lead O2 sensor(s) (sensor 1) sends a varying voltage to the PCM several times a second. When the oxygen content of the exhaust stream is

2010/7/11(日) 午後 3:08 [ 車QF ]