OBD Not Ready - Need Thoughts/Advice Please

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2021 CX-5 GT-R
I took my p5 in to get the safety/emissions tests and they told me that my OBD (On Board Diagnostic) wasn't ready to be tested.

The results came back as:

Catalyst: not ready
O2 Sensor: not ready
EGR Sys: not ready

The guy told me that my system just needs to reset itself so I should drive it around and come back. I drove it for 30 miles and brought it back the next day and got the same results. He told me to drive it more and bring it back again so I guess I'm going to do that and take it back in a few days.

He said this is somewhat common if recent work has been done or if the battery has been unplugged, but I haven't unplugged the battery for months.

I did just get my oil changed at Jiffylube the day before I took it in to get tested, but I don't think they unplugged the battery.

I did have an electrical problem a few months ago and had to take it to mazda because it was grounded improperly, so they grounded some main wires for me properly. Not sure if that would effect this or not.

Anyways, does this sound fishy at all, like I'm going to be spending some money to get this taken care of, or is it somewhat common and I should just drive it around more? 30 miles seemed far enough to me.
 
I work at one of the emissions stations here and we see it all the time. Usually giving it a few days of normal driving will reset the computer.


I've been told by a mechanic friend that if a car has a fault code (or multiple) pending that can also prevent the monitors from setting.
 
It takes ~50 miles for the ECU to readjust itself after being reset (unplugged). If it's been longer than that, I would move on to the next step. If it had a fault code, the diagnostic machine would know.

The reason you see that a lot at emmisions testing, is because thats the easiest way to beat the test... lol
 
Yes, if it had a code set & stored in the memory it would get picked up. A pending code hasn't been set and won't be seen by the computer used for the test. Having the car 'not ready' is not a way to beat the test at all. We don't test the car in that situation. We send them on down the road for the computer to set and either pass or fail if they were clearing a code.
 
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It's all about selling yourself. And getting lucky. :)

I'm just saying, that people try to reset their ECU in hopes of beating the emissions tester... Whether it works or not is dependent on the technician, and having a nice pair of tits helps too... :D
 
Do you have a CEL? Are you letting it warm up sufficiently before taking it in?

I've never gotten a CEL with this car and I've had it for over a year. When I drove it 30 miles for the test, I drove right to the station after I hit 30 miles, so it was plenty warm.

I did buy the car as a rebuilt title. It was in a front end collision. Could the CEL be messed up, or would that come through in tests as well?

It takes ~50 miles for the ECU to readjust itself after being reset (unplugged). If it's been longer than that, I would move on to the next step. If it had a fault code, the diagnostic machine would know.

The reason you see that a lot at emmisions testing, is because thats the easiest way to beat the test... lol

I guess I'll drive it around more for a few days. What is the next step if driving around more doesn't work?
 
There are a certain number of cycles the ECU has to go through before it will be "ready". Most code scanners have a "state test" or something that will tell you if it will pass or not.

If it fails again, get it scanned by someone who has a clue.
 
Does the CEL come on when you first start the car (test)? Bulb may have been removed or it burned out and you do have a code ...
 
Does the CEL come on when you first start the car (test)? Bulb may have been removed or it burned out and you do have a code ...

The CEL comes on when I start the car I just noticed, so that's good.

I'm driving it around a bunch more and will take it back next week and see how it goes.
 
Well, it's been over 900 miles now, a new Mass Airflow Sensor (mazda told me I had a broken one), still have never gotten a CEL, but it's still saying, "Not Ready".

Mazda told me everything looks fine and they can't find any indications of a problem and they don't know why I'm not getting a CEL in all of this.

Any suggestions?
 
Well, it's been over 900 miles now, a new Mass Airflow Sensor (mazda told me I had a broken one), still have never gotten a CEL, but it's still saying, "Not Ready".

Mazda told me everything looks fine and they can't find any indications of a problem and they don't know why I'm not getting a CEL in all of this.

Any suggestions?

Make friends with another protege owner and swap ECUs :)
 
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