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Part 2: Why the SMOG test on a new vehicle and what the hell are monitors?
All automotive dealerships in California are governed by California Law and expressly forbidden from installing any non-CARB compliant device or modification - or risk facing SEVERE penalties. However smog laws in different states vary - and none of them are governed by California law. For example, let's say a dealership in Texas will install headers on your new Mustang and include that cost in the financing of the vehicle. (Lets assume that legal in Texas.) Well, although the Mustang may be new and 50-state SMOG compliant, it is no longer compliant with the laws of California. Therefore, CA requires that ANY new car brought in from out of state must first pass a CA smog test by a certified station (which also, of course includes a visual inspection.)
As part of the Federal OBD2 standard, the ECU of modern day vehicles is responsible to insure that the vehicle is in compliance with emissions laws and STAYS in compliance throughout its intended life cycle. As such, the ECU will periodically run tests to make sure everything is hunky-dory. These tests include but are not limited to Catalyst, EGR, and EVAP - these are the ones that CARB cares about. As a car ages, one day maybe the cats are no longer effective and the ECU's responsibility (Federal requirement) is to detect this and turn on the check engine light - telling the owner to get it fixed. Another example is the fuel or EVAP system. Ever hear of a CEL because the fuel cap is off or not tight? This is because the EVAP test fails, thinking there's a massive hole in the fuel system releasing deadly toxins into the air and killing the last of the unicorns. I digress.
So, the ECU has something called monitors. Each of "big 3" that I mentioned, CAT, EGR and EVAP will have an associated monitor. The monitor simply states that the internal ECU test has run. As a brand new car, none of the monitors will be set (none of the internal tests have run). The ECU needs to "see" certain conditions before it will decide to run the test. Sometimes it can be frustrating for owners trying to get their monitors to "set". The most common occurrence is after changing the battery. Changing the battery will cause all of the monitors to un-set. Ford has openly published their recommended drive cycle for setting the monitors. It can be found HERE.
When you take your new Bronco or any other car to a CA Smog Test station, the first check is to see if the monitors have been set. If any(*) of them are not set, you will be sent on your way. But if the monitors are all set AND there is no check engine light - then the smog station knows that the test MUST have passed. That's literally all of what the CA smog stations are doing. They connect to your OBD2 port and their machine is connected to Sacramento and they read your ECU. They are looking to insure that all of the monitors are set and that there is no active or pending check engines lights.
Hope all of that helps - likely more than you wanted to know.
(*) - subject to change, but CA will currently allow a vehicle to pass smog if the EVAP monitor is not set - as long as all of the others are good.
All automotive dealerships in California are governed by California Law and expressly forbidden from installing any non-CARB compliant device or modification - or risk facing SEVERE penalties. However smog laws in different states vary - and none of them are governed by California law. For example, let's say a dealership in Texas will install headers on your new Mustang and include that cost in the financing of the vehicle. (Lets assume that legal in Texas.) Well, although the Mustang may be new and 50-state SMOG compliant, it is no longer compliant with the laws of California. Therefore, CA requires that ANY new car brought in from out of state must first pass a CA smog test by a certified station (which also, of course includes a visual inspection.)
As part of the Federal OBD2 standard, the ECU of modern day vehicles is responsible to insure that the vehicle is in compliance with emissions laws and STAYS in compliance throughout its intended life cycle. As such, the ECU will periodically run tests to make sure everything is hunky-dory. These tests include but are not limited to Catalyst, EGR, and EVAP - these are the ones that CARB cares about. As a car ages, one day maybe the cats are no longer effective and the ECU's responsibility (Federal requirement) is to detect this and turn on the check engine light - telling the owner to get it fixed. Another example is the fuel or EVAP system. Ever hear of a CEL because the fuel cap is off or not tight? This is because the EVAP test fails, thinking there's a massive hole in the fuel system releasing deadly toxins into the air and killing the last of the unicorns. I digress.
So, the ECU has something called monitors. Each of "big 3" that I mentioned, CAT, EGR and EVAP will have an associated monitor. The monitor simply states that the internal ECU test has run. As a brand new car, none of the monitors will be set (none of the internal tests have run). The ECU needs to "see" certain conditions before it will decide to run the test. Sometimes it can be frustrating for owners trying to get their monitors to "set". The most common occurrence is after changing the battery. Changing the battery will cause all of the monitors to un-set. Ford has openly published their recommended drive cycle for setting the monitors. It can be found HERE.
When you take your new Bronco or any other car to a CA Smog Test station, the first check is to see if the monitors have been set. If any(*) of them are not set, you will be sent on your way. But if the monitors are all set AND there is no check engine light - then the smog station knows that the test MUST have passed. That's literally all of what the CA smog stations are doing. They connect to your OBD2 port and their machine is connected to Sacramento and they read your ECU. They are looking to insure that all of the monitors are set and that there is no active or pending check engines lights.
Hope all of that helps - likely more than you wanted to know.
(*) - subject to change, but CA will currently allow a vehicle to pass smog if the EVAP monitor is not set - as long as all of the others are good.
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