CanOBD2 Reader and my Cavalier
bulletworm
04-09-2007, 05:10 PM
I bought a code reader recently to help solve some problems with a Windstar and decided to give it a run on my 2000 Cavalier as well, just in case.
After reading the on-board computer, the scanner remains yellow, even though there are no error codes. Further investigation reveals that means that one or more systems have not reported testing as being 'completed.'
Now some background: My little 'go cart' (as I like to call it) has not had any problems in quite some time, other than regular maintenance issues that is.
I haven't had it worked on in over a year, when I had a fuel pump go out. Not even a battery replacement...
However, despite that, my code reader is 'flashing' on all of the following:
'c' --> Catalyst Monitor
'o' --> Oxygen Sensor Monitor
'oh' --> Oxygen Sensor Heater Monitor
'ev' --> EVAP System Monitor
The flashing is supposed to indicate that testing has not completed even though these are supposed to be tested 'once per trip' of which I have PLENTY of...
Any idea on what could be the problem?
Danny
After reading the on-board computer, the scanner remains yellow, even though there are no error codes. Further investigation reveals that means that one or more systems have not reported testing as being 'completed.'
Now some background: My little 'go cart' (as I like to call it) has not had any problems in quite some time, other than regular maintenance issues that is.
I haven't had it worked on in over a year, when I had a fuel pump go out. Not even a battery replacement...
However, despite that, my code reader is 'flashing' on all of the following:
'c' --> Catalyst Monitor
'o' --> Oxygen Sensor Monitor
'oh' --> Oxygen Sensor Heater Monitor
'ev' --> EVAP System Monitor
The flashing is supposed to indicate that testing has not completed even though these are supposed to be tested 'once per trip' of which I have PLENTY of...
Any idea on what could be the problem?
Danny
spudracer73
04-10-2007, 11:23 PM
the monitors don't all run at once on the same trip. there are "drive cycles" that have to be completed inorder to test each system and then after the systems are tested the monitor problem will go away. There is no problem with your car. If you unplugged the battery recently then the monitors would have been clear and the pcm needs to run test on those monitors again to gain "OBD II" readiness.
bulletworm
04-11-2007, 11:12 AM
the monitors don't all run at once on the same trip. there are "drive cycles" that have to be completed inorder to test each system and then after the systems are tested the monitor problem will go away. There is no problem with your car. If you unplugged the battery recently then the monitors would have been clear and the pcm needs to run test on those monitors again to gain "OBD II" readiness.
Thanks for the response!
I understand what you are saying, but I have not removed battery power from the Cav in over a year. I live in Houston, so no problems with climate and being too cold for tests either.
However, this has made me think about ONE item: I removed the fuse that controls the clutch for my air compressor (went out at the end of last summer and kills the car if it trys to turn on). I wonder if that same circuit also provides power to these components. I would hope not, but I suppose it is a possibility.
Danny
Thanks for the response!
I understand what you are saying, but I have not removed battery power from the Cav in over a year. I live in Houston, so no problems with climate and being too cold for tests either.
However, this has made me think about ONE item: I removed the fuse that controls the clutch for my air compressor (went out at the end of last summer and kills the car if it trys to turn on). I wonder if that same circuit also provides power to these components. I would hope not, but I suppose it is a possibility.
Danny
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