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Failed smog check due to monitors not self-testing?

(2002 Toyota Highlander)
in Chula Vista, CA on November 28, 2009
My highlander has under 100,000 miles on it. I just got back from a smog check, and while my car passes all of the emissions tests, it failed because the computer has not finished all of its monitor self-tests for some reason. I had the battery changed about six months ago, so, according to the technician, it should have certainly gone through all of the self-checks by now. I called the dealer about this and they want to charge me a minimum of $100 to diagnose it.

What do I have to do to make the computer go through all of its self-checks so that I can pass my smog test?

Any help appreciated.
Displaying 1 answers & 2 comments
Popular Answer
on November 29, 2009
There is something that is not working correctly in your Monitor System. If you have an emission component that is border line, like your CAT or an Oxygen Sensor, the Monitors will not set. Did you ever replace your CAT because if so, you may need a software update. And if it was not a factory CAT, the monitors will almost never work correctly.There is a large Technical Service Bulletin (23 pages) number EG003-02 about how set the Monitors for your vehicle, so Toyota knows about this issue. The best thing to do is to have a skilled Technician, first run this procedure and then check your Mode 6 data. This is pretty technical stuff, in that it is hexadecimal scientific data on the status of your your Emissions Monitors, Components and test IDs and results. I would NOT go to a dealer, because they often don' t do Smog. I do Gold Shield Smog Emissions work in N. California for a living. I would go to the best Gold Shield Shop in your area. Gold Shield Shops are required to know how to check Mode 6, which most shops and dealers are clueless about. I have to fix cars for the big Toyota dealer just across the Street from my shop every week, because they are lost. Dealers are often just parts replacement shops and not very good at serious Diagnostic any more.
on November 29, 2009

Thanks for your detailed response. I took it back to the center and the Tech said only the evaporative system monitor is not working.

Do you know how to reset this evaporative system monitor?

thanks again.
on September 05, 2010
If a monitor has not ran for evap you eather haven't waited long enough or the system is not sure if it will pass. You need to have it checked for pending codes. A code will set after the monitor sees a problem twice in a row. The problem may happen that will cause a pending code but then not happen again untill the computer clears the pending code. I do alot of evap related problems for the dealersa and some shops in my area. Sometimes it is very frustrating. Funny but the biggest problem with getting a evap monitor to run is that every time it is about to clear the customer stops and gets fuel and doesn't tighten the gas cap wich causes the evap monitor to see a problem and reset a pending code. Also most hand held scanners do not show pending codes. Note , If you don't have a lite on but you do have a pending code . DO NOT RESET THE PC TO CLEAR THE PENDING CODE. That will only clear all of the monitors. Most of the time you just have to be patient.
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