0420 Code for 2002 Camry LE V6

My check engine light came on and the code was 0420. The car runs fine and aside from the light, I don't feel anything is wrong. I had the mechanic turn the light off.

Any thoughts on what it could be? Something to do with 02 Sensor/Cat on Bank 1 I believe.

Reply to
Car Guy
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P0420 Catalyst System Efficiency Below Threshold (Bank 1)

Try this link,

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or useyour favorite search engine to look for "OBD II Codes". I don't know what can make the efficiency be below the threshold, but my first guess would be the sensor itself. The CAT can be toast, but I would not expect it to be bad at this point in your car's life. This is an emmission system item, and should be covered by the warranty.

Reply to
Jeff Strickland

what are the symptoms of a bad cat convertor or oxygen sensor? I passed my drive clean emission by a WIDE margin 2 weeks ago. The dealer said I need a firmware upgrade for the CPU

Reply to
Car Guy

Cat is degrade by 60% or better. It will come back on

Reply to
Liberals=Angry Losers!

Your car is a 2002, so you will find the OBD II data port along the underside of the dashboard, in the vicinity of where your left leg is while driving. The port looks sorta like a printer port (on the printer, not on the computer), except it only has something like 16 pins instead of the printer's 40 pins. The shape of the pins and the connector look like the back of a printer, but there aren't as many pins.

Anyway, many auto parts stores have the OBD II code reader in stock, and you can check it out - like a book from the library. Use the code reader to reset all of the codes, then don't worry unless the Check light comes back on AND it throws another P0420.

It is conceivable that you would need a firmware upgrade, but if the logic is that the computer is an emission system component, then the firmware should be a free upgrade during the emission system warranty period. For the firmware to be the problem, then there is nothing wrong with the car, but the check for whatever this sensor is telling you has a window tha tis too small, and the firmware will make the window larger to prevent false reporting of this particular error. If you reset the light, then the odds are that it will not come on again for a very long time, and this would tend to point to firmware errors causing a false report.

Reply to
Jeff Strickland

Thanks Jeff.

I went to the local garage and his brother works at the dealership and told me that since the car is running fine, the computer needs a firmware update.

I had the light reset and so far, it has not come on yet. If it does, and as you said, I get the same 0420 code, then I will get the firmware upgraded to the cost of $100. Since the car now has about 70,000 miles on it, it is out of warranty and this is a "grey" area under the ECP Toyota warranty.

So far, I have had the Check Engine light come on 2 times : Shift Solonoid Malfunction, and when the Throttle Body was frozen. Both times it was fixed in warranty and under ECP and the repair bills were $2400 and $1500 respectively.

Needless to say, when that light comes on, I think "oh crap, there goes $1K!"

Reply to
Car Guy

A 4:20 code?

Reply to
B a r r y

Your Emissions System Warranty runs for miles or time, WHICHEVER TAKES LONGER. You are nowhere near the time, and the firmware upgrade should be free. Stomp your feet and get red in the face and demand that the emissions system is malfunctioning and should be repaired - whatever it takes - under the warranty that is there specifically to protect you from this sort of failure.

The whole point of the warranty is that the consumer is open to huge repair bills from a federally mandated system that is by its very nature prone to a hostile operating environment. The manufacturers are required to make the system withstand the hostility, and yours seems to be prone to problems that can be corrected by a simple firmware upgrade. It takes a matter of a few minutes to load new firmware, and the alternative for the dealership is to fix hardware so it complies with the small window tha tthe firmware demands. They (apparently) found that there was a significant number of repairs to whatever the P0420 reports, and the timing window was too small. The way they figure this out is by taking the stuff back that is repaired under warranty and then testing it. The sensor that reports the P0420 errors could have been found to be within spec, but the ECM is still reporting the error. The fix is to open the window for which the sensor can come up to speed, so to speak.

In any case, just because you have gone over the waranty period - in miles - for the rest of the car, you have not gone over the waranty period - in time - for the emissions system.

Reply to
Jeff Strickland

Warranties expire at a given time or mileage, whichever comes first, not whichever takes longer.

Reply to
Ray O

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