Our customer’s 1999 Toyota Camry CE 2.2L failed the biennial smog check inspection (category: OBD System Checks for being “Not Ready“). In most situations driving the vehicle for a week or two (streets & highway) will allow the vehicle to complete it’s self tests (readiness monitors) and become “Ready” so that it will pass the emission inspection.
Unfortunately, our customer drove almost 500 miles and still his Toyota was Not Ready for the following three monitors: Catalyst, Oxygen Sensor & Oxygen Sensor Heater.
He asked us to diagnose the problem. Although there was no check engine light illuminated, there as a pending diagnostic trouble code (DTC) stored in the vehicles computer: DTC P1155. P1155 is a manufacturer specific code relating to the Air/Fuel Ratio Sensor Heater Circuit.
Our technician diagnosed the air/fuel sensor and confirmed an open heater circuit. We replaced the a new Denso air/fuel sensor, cleared the fault code, and drove the vehicle.
In less than 20 miles of our drive cycle all three incomplete monitors (Catalyst, Oxygen Sensor & Oxygen Sensor Heater) became “Ready”. We re-tested the Camry and it passed.
Although in most “Not Ready” failed smog check situations, a vehicle can be driven to become “Ready” and pass a California smog inspection, repairs are sometimes necessary.
HELP, my check engine light is on because of a P0420 fault code.
The P0420 code means that the vehicle’s computer has detected that the three-way catalytic converter is not working properly (is not as efficient as the factory is expecting). This does not necessarily mean that you have to replace the catalytic converter to fix the problem. Replacing the oxygen (O2) sensors may sometimes fix the code because the vehicle’s computer interprets data from the oxygen sensors to determine if the catalytic converter is working properly.
If the catalytic converter is in fact defective, you must replace it with either a factory (OEM) converter or a California Air Resource Board (CARB) approved aftermarket converter. Be sure that the aftermarket converter is the correct part by confirming:
- Year/Make/Model/Engine Size
- Test Group Name or Engine Family Number *
- Manufacturer Part Number
- Executive Order Number
- Converter Location
* Exception: Federally certified vehicles (Non-California) may not have a matching Test Group/Engine Family number listed on the Aftermarket Catalytic Converter Database. So as long as all other criteria matches, the converter should be approved for the application.
If there are no options listed for your vehicle application on the Aftermarket Catalytic Converter Database, an OEM converter is required.
Many mechanic & muffler shops mistakenly install incorrect converters. If you are unsure, feel free to contact us with any questions.
** This information is accurate as of July 2016. For the most up-to-date rules and regulations, please contact the California Air Resource Board.
The catalyst monitor on many Toyota vehicles can be difficult to complete. That’s why it’s important to follow the Toyota recommended drive cycle after performing actions that are known to clear your Toyota’s computer memory.
Remember, all on-board diagnostic monitors are cleared when the battery is disconnected, or when the power train control module (PCM) is cleared with a scan tool.
CATALYST MONITOR DRIVE CYCLE INSTRUCTIONS
- Do not turn off the ignition switch during the test procedure.
- Allow the vehicle to run at idle until warmed up.
- Drive at a steady speed between 40 and 70 MPH for 10 minutes. It’s a good idea to stay in the middle of this range, so 55 MPH is optimal.
- It may take several attempts and warm up cycles to complete the drive cycle.
This 2008 Toyota Prius Hybrid passed its change-of-ownership smog check inspection today at JUST SMOGS® in Huntington Beach. Hybrid emission inspections are essentially the same as most 2000 and newer gasoline powered vehicles.
The inspections consists of a comprehensive visual inspection of the emission systems as well as an OBD computer scan.
OBD II is a system that has been installed in most 1996 and later cars and light trucks, intended to inform the driver of problems in the components that control the engine and transmission. The primary reason OBD II was invented is to reduce smog emissions caused by malfunctions, but it is also valuable as an alert to the driver that something is wrong…something that can affect gas mileage and drivability, or actually cause further damage to the vehicle.
This beautiful Ferrari 360 Spider passes a STAR smog check inspection. Licensed smog technician John takes special care during the inspection.
Our smog technicians are inspecting two very different vehicles. The Aston Martin Vanquish passes it’s star smog check. Unfortunately, the 1977 Volkswagen Bus does not. It is sometimes difficult for older vehicles to conform to the strict smog standards set out by the State of California. On the bright side, California offers subsidized smog repairs for low-income motorists. There is also a vehicle retirement program that will give you cash for your “clunker.”