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Remove battery. took it to smog fail because the monitors were not set

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If the check engine light was on before you disconnected the battery you will need to address that issue before the monitors will reset. If there was no check engine light driving a combination of city and freeway for a day should reset all monitors

Posted on Dec 31, 2013

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Reset computer on 2002 ford expedition. fuel pump has been replaced and has new battery. need to pass smog.

What ? the monitors aren't set ? Need to do drive cycle to get them to set . Do you have a check engine light lit ?

Ford Motor Company Driving Cycle

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2001 chevrolet tahoe secondary air system not working cant pass smog all I did was replace battery before getting it smog

Disconnecting the battery resets the PCM - engine computer ,an the emission monitors . A drive cycle has to be done to get the monitors to run an hopefully set. That's all you need to do is drive it for few days of different driving conditions - city , highway ,from cold start . google GM drive cycle . OBD Monitor Not Ready

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After disconnecting my battery to change my starter, I went to get a smog. It was rejected. What drive cycle do I need to clear the system? Vehicle is 2005 Saturn Vue. 4 cyl,two whl drive, 5 spd man.

It should not take a very long drive cycle for the PCM to recover a full relearn. What part of the smog failed? CO? CO2? You may need a scan tool connected to monitor sensor activity to find out what is causing the emissions to fail

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What does po 300+ mean? Misfire i know.

You might try replacing the PCV valve. . .just a thought.

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My CE light is on. The code is PO420. It is a 2002 Corolla. Smog is due. Two years ago, the same thing happened. I bought a scanner, cleared the light. Took it to smog. Passed. But this year, I cleared...

The P0420 is for the catalyric converter, you'll have to have it replaced. It will fail the test as long as the light is on. Clearing the code information also clears the monitor infor, to pass the monitors required you'll have to put some miles on it in both city and highway driving, not all monitors may be required so check with your local smog station which ones have to pass.

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I have a 2002 Chevy Cavalier. The engine light came on and it was the catilac convertor that needed to be replace. Mechanic completed the job and now the engine light is off. Took the car in for...

They are refering to the Drive Cycle not being completed. There are 7 monitors that have to complete in order for them to have a passing signal where the Smog Tech / Smog Machine can say its a pass in that part of the test.

This is what you need to do hope it helps out.

Cold Start
  • The barometric pressure (BARO) is more than 72 kPa .
  • The engine coolant temperature (ECT) is below (84°F ).
  • The intake air temperature (IAT) is below(84°F ).
  • The difference between the IAT and the ECT is(13°F ) or less.
  • The battery voltage is between 9.0-16.0 volts .
  • The fuel level is between 1/4 and 3/4.

Inspection/Maintenance (I/M) Complete System Set Procedure - Steps 1-4 155390324

If you have more questions let me know. Good Luck.

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Failed CA smog test "MIL/Check Engine Light", computer data wiped

No this is not right. If you remove the battery everything resets anyways. If they are talking about relearn procedure, it should only require 50 miles. But if the light is on than either they did something wrong, created another problem, or there was already another one existing. Have the code read and let me know what it is. I'm in Ca too and used to prep european cars for smog, so I do know what I'm looking for. How did the rest do? What were the readings(if possible)?

May 20, 2010 | 2003 Chevrolet Suburban 1500

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My 1997 saturn SL1 wont pass a smog test..was told when I changed the battery it messed up the computer and I need to reset the computer. How do I do this?

Only service station can reset.If your check engine light is on go to a Pep Boys or auto barn most will read the computer diagnostic for free.( $ 5-10 ) tip might get them to reset it,might.I don't know what a service station charges $ 75 ? good luck

Sep 05, 2009 | 1997 Saturn SL

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1996 Nissan Maxima GXE Fail Smog Check Due To ECM System Failure

There is no way to fix this issue according to my Nissan Dealer Service Manager. The monitors will not run and therefore the vehicle will not pass smog. If you need assistance from California's SMOG authority they are called "The Referee" and you can call them at 1-800-622-7733.

Feb 11, 2009 | 1996 Nissan Maxima

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