OBDII: CAT_RDY INC and O2S_RDY INC

[biomecanoid]

Hello,

I have a 2006 Daihatsu Sirion ( Same car as Toyota Passo ) I have for about 3-4 months now a CAT_RDY INC under I/M Readiness. NO errors codes or check engine light.
Today I realized on top of that I have a O2S_RDY INC.

Car is running fine good acceleration, good top speed. Only thing I have noticed is a bit higher fuel consumption.

The only thing that I did today is take the car for the yearly oil change and since its weekend and I have some free time I did some checks on the car: Fluids, Battery, Tyre pressure etc and when I connected the OBDII I found I have one more I/M Readiness INC.

When I took the car to the mechanic for the oil change I told him I have a CAT_RDY INC and without looking at the car he told that the O2 sensor need replacing. After I took the car back from the mechanic the O2S_RDY INC popper up in OBDII. Coincidence ?

What needs to be done now ? Replace the CAT and O2 sensor ? thats like 1000$ job and recommendations ?

 

[mk378]

The ECU needs to have backup power while the key is off. If you disconnect the battery, or the backup circuit fuse is blown, these not ready codes will be set. They go away by themselves after a period of driving, called a "drive cycle". In some cases the car has to be driven in specific ways to complete the cycle. This will be in the service manual.

Not ready means that the car has not been run enough since the last memory reset to make a conclusion whether the sensor is good or bad. It doesn't mean that the sensor is bad.

 

[Gimpy1]

The ECU needs to have backup power while the key is off. If you disconnect the battery, or the backup circuit fuse is blown, these not ready codes will be set. They go away by themselves after a period of driving, called a "drive cycle". In some cases the car has to be driven in specific ways to complete the cycle. This will be in the service manual.

Not ready means that the car has not been run enough since the last memory reset to make a conclusion whether the sensor is good or bad. It doesn't mean that the sensor is bad.

Exactly the vehicle needs to go thru certain parameters in order for the self test and readiness to set. Typicaly the evap one is the hardest to set thats why you can fail one and still pass state inspection (at least in Texas)

 

[biomecanoid]

The ECU needs to have backup power while the key is off. If you disconnect the battery, or the backup circuit fuse is blown, these not ready codes will be set. They go away by themselves after a period of driving, called a "drive cycle". In some cases the car has to be driven in specific ways to complete the cycle. This will be in the service manual.

Not ready means that the car has not been run enough since the last memory reset to make a conclusion whether the sensor is good or bad. It doesn't mean that the sensor is bad.

I have the CAT_RDY INC for about 4 months now. and I have not disconnected the battery during those 4 months, Isn't that too long a wait ? The O2S_RDY INC just appeared today.

Is this an issue that should be addressed immediately ? The mechanic I think is trying to scare me by saying if I don't change the O2 Sensors which is about 500$ job it will damage the car resulting the car going into safe in the long run.

I don't perceive the issue being so serious if it was something critical I should be getting error codes which I don't have. Correct ?

 

[partspro]

My 2 cents on monitor ready, upstream O2 toggles, little rich and then lean, good for 3-bed CAT, Downstream O2 checks catalyst efficiency, and o some vehicles can affect air/fuel ratio at startup before transitioning to closed loop. The INC status says 2 readiness monitors failed to complete, and yes, the car COULD go into limp mode to prevent damage to catalytic converters. I would fix it, the higher fuel use is because ECU has incomplete data to work with so trends rich.

 

[Gimpy1]

No codes, readiness is set whats the issue? There is nothing wrong, leave it alone its fine. Ready means everthing is good to go stop worrying, you are tring to fix something that isnt broken. Google "what does ready mean in OBD 2"

 

[biomecanoid]

No codes, readiness is set whats the issue? There is nothing wrong, leave it alone its fine. Ready means everthing is good to go stop worrying, you are tring to fix something that isnt broken. Google "what does ready mean in OBD 2"

I have the CAT_RDY INC for 4 months now and its not going away. Yesterday I found out that I also have O2S_RDY INC. Doesn't that mean that things are getting worse over time and eventually I will get error codes for O2S or CAT ?

 

[biomecanoid]

My 2 cents on monitor ready, upstream O2 toggles, little rich and then lean, good for 3-bed CAT, Downstream O2 checks catalyst efficiency, and o some vehicles can affect air/fuel ratio at startup before transitioning to closed loop. The INC status says 2 readiness monitors failed to complete, and yes, the car COULD go into limp mode to prevent damage to catalytic converters. I would fix it, the higher fuel use is because ECU has incomplete data to work with so trends rich.

I have CAT_RDY INC and O2S_RDY INC. what should be addressed 1st ? change the catalyst ? or change the O2 Sensor ?

 

[biomecanoid]

Well I am getting conflicting information here partspro says fix it, Gimpy1 says its nothing

 

[Gimpy1]

What are you going to repair? There is no code it says ready. You never replace parts based on a dtc, of which you have none. Go ahead replace your entire emissions system. INC means incomplete which means it hasn't completed the necessay drive cycle to set condition, not that a sensor or part is wrong. You are using a very basic scan tool to improperly diagnose a complex emission system, this is like getting your blood pressure checked at the mall then going to get a heart transplant because the machine said you had high blood pressure. If your vehicle is running fine and passes emissions leave it alone. These cheap scan "tools" are great as diagnostic starting points, but you need way more diagnosis before replacing very expensive parts.

 

[biomecanoid]

What are you going to repair? There is no code it says ready. You never replace parts based on a dtc, of which you have none. Go ahead replace your entire emissions system. INC means incomplete which means it hasn't completed the necessay drive cycle to set condition, not that a sensor or part is wrong. You are using a very basic scan tool to improperly diagnose a complex emission system, this is like getting your blood pressure checked at the mall then going to get a heart transplant because the machine said you had high blood pressure. If your vehicle is running fine and passes emissions leave it alone. These cheap scan "tools" are great as diagnostic starting points, but you need way more diagnosis before replacing very expensive parts.

OK so the mechanic that told me it is imperative to change the O2 sensor or the car will go to safe/limp mode is lying ?

 

[Gimpy1]

Maybe IDK, I or anybody here can form a diagnosis based on the information you have provided. It could well be a lazy O2 sensor or a Cat, its anyones bestguess. What I'm trying to tell you is dont throw parts at a problem, a proper dianosis is needed. Your problem may temporarily go away but replacing parts, but if the real issue isn't fixed you are going to have the same issue over and over again.

 

[biomecanoid]

Maybe IDK, I or anybody here can form a diagnosis based on the information you have provided. It could well be a lazy O2 sensor or a Cat, its anyones bestguess. What I'm trying to tell you is dont throw parts at a problem, a proper dianosis is needed. Your problem may temporarily go away but replacing parts, but if the real issue isn't fixed you are going to have the same issue over and over again.

OK understood

 

[biomecanoid]

This is all the readings from the OBDII after a slow 20min drive

 

[biomecanoid]

Hello do you consider cleaning the O2 Sensor with Carb cleaner safe ? Like in this video ?

 

[Job]

Not ready happens anytime the battery is disconnected etc, it doesn’t mean anything is wrong. Throwing away money on parts because the reader says it’s the o2 sensor etc is very common. The sensor may be fine, probably is fine, something can be messing up the signal the sensor is putting out and then the computer throws o2 sensor code. It could be an air leak in the intake system or something else. If the MAF tells the computer data, then there is an air leak after the MAF, the computer throws a code the o2 sensor is wrong. The o2 sensor can still be perfect. Mechanic isn’t lying, lying is purposely making something up. Being wrong is not lying.

 

[mattd]

Unless you are trying to get the car to pass a plug in emissions test leave it alone until it throws a DTC.

 

[biomecanoid]

Not ready happens anytime the battery is disconnected etc, it doesn’t mean anything is wrong. Throwing away money on parts because the reader says it’s the o2 sensor etc is very common. The sensor may be fine, probably is fine, something can be messing up the signal the sensor is putting out and then the computer throws o2 sensor code. It could be an air leak in the intake system or something else. If the MAF tells the computer data, then there is an air leak after the MAF, the computer throws a code the o2 sensor is wrong. The o2 sensor can still be perfect. Mechanic isn’t lying, lying is purposely making something up. Being wrong is not lying.

OK if it is an air leak what should I be looking for to verify that ?

 

[biomecanoid]

Unless you are trying to get the car to pass a plug in emissions test leave it alone until it throws a DTC.

So this is not a good idea to perform as a preventative measure ?

 

[mattd]

No