We bought a 2003 Pathfinder, SE 4x4 back in December. Not too long after the purchase the throttle body/throttle position sensor quit. No big deal, only $130 and easy to swap out. Only to find out I needed to perform an Idle Air Volume Learn and found instructions here and elsewhere. Attempted several times and it did not work. Through searching I found Nissan Data Scan software and have attempted to perform the IAVL with both a tablet and a laptop, both continue to fail. I figured out that the reason it is failing (assumed?) is that the vehicle speed is not registering zero when stopped and the transmission in park, the software is indicating 6mph!
According to the factory service manual, the speed signal comes from the ABS control electrical unit.
Has anyone else run into something like this and found a solution? I have not run the self diagnostics on the ABS yet and maybe there will be clues there, until then I am getting 10mpg and continuing to clear the SES light for high idle.
Idle Air Volume Learn Fails
Re: Idle Air Volume Learn Fails
I have not heard of that. Maybe there is a problem with your software?
You may be able to cheat a little by pulling the ABS fuse or disconnecting the ABS connector at the unit. This should result in 0 mph in your software, since there will be no speed signal from the disconnected abs. Then try to do the idle relearn.
There is a combination meter self test diagnostic mode in the EL part of the manual if you do have a problem. Also look up p0500 VSS error in the EC section - that is the speed signal that goes to the ABS.
For the mileage - how old are your plugs? Also, cleaning the MAF may be of some help.
You may be able to cheat a little by pulling the ABS fuse or disconnecting the ABS connector at the unit. This should result in 0 mph in your software, since there will be no speed signal from the disconnected abs. Then try to do the idle relearn.
There is a combination meter self test diagnostic mode in the EL part of the manual if you do have a problem. Also look up p0500 VSS error in the EC section - that is the speed signal that goes to the ABS.
For the mileage - how old are your plugs? Also, cleaning the MAF may be of some help.
Re: Idle Air Volume Learn Fails
Thanks Rockwood, I will try pulling the fuse for the ABS and or the wiring connector. I did try pulling the connector for the VSS at the back end of the transmission front of the transfer case. That did not work, still showed 6mph and immediately threw a code, P0720 if I remember correctly. I think the P0500 code is turbine speed sensor at the front of the transmission, correct?
I think most of the millage issue is the idle air volume learn, or at least I remember running across a post somewhere where the owner was able to set the idle air he said his fuel mileage improved and was great, can't find that thread again through.
This Pathfinder is new to me (my third) and I am slowly going through it making sure all fluids are refreshed and doing the tune up items along the way. I have not gotten to the spark plugs yet so there is an unknown number of miles on them.
I think most of the millage issue is the idle air volume learn, or at least I remember running across a post somewhere where the owner was able to set the idle air he said his fuel mileage improved and was great, can't find that thread again through.
This Pathfinder is new to me (my third) and I am slowly going through it making sure all fluids are refreshed and doing the tune up items along the way. I have not gotten to the spark plugs yet so there is an unknown number of miles on them.
Re: Idle Air Volume Learn Fails
Looking up the codes a p0500 is vehicle speed sensor, the p0720 is for that circuit. It makes sense you got that code when you unplugged the sensor.
However, in reading up on p0500, it talked about an "almost 0 km/h signal" which I had never heard of. I googled that, and came up with one post about a Yukon at this link:
http://www.justanswer.com/gm/7up7z-gm-2 ... -when.html
The post says it is ok not to have a 0 mph reading. That kind of implies your reading may be ok. I think there are some preconditions in the manual that have to be met for the IAVL procedure to work. See if you can find those in the manual, and make sure you are ok on those. One thing I think you have to do is make sure your Drive Cycle and Emissions Readiness Monitors all show ready.
Also, did you do the throttle position sensor adjustment after you put a new one in? There is a procedure for that in the manual.
Three Pathfinders - that may qualify you as an addict!
However, in reading up on p0500, it talked about an "almost 0 km/h signal" which I had never heard of. I googled that, and came up with one post about a Yukon at this link:
http://www.justanswer.com/gm/7up7z-gm-2 ... -when.html
The post says it is ok not to have a 0 mph reading. That kind of implies your reading may be ok. I think there are some preconditions in the manual that have to be met for the IAVL procedure to work. See if you can find those in the manual, and make sure you are ok on those. One thing I think you have to do is make sure your Drive Cycle and Emissions Readiness Monitors all show ready.
Also, did you do the throttle position sensor adjustment after you put a new one in? There is a procedure for that in the manual.
Three Pathfinders - that may qualify you as an addict!
Re: Idle Air Volume Learn Fails
Well, I figured it out. the new throttle body is faulty. I went through all the required parameters again. I realised that the IAVL needed the idle speed to drop to 750rpm or lower. It was only dropping to about 800rpm, close but not close enough. I choked off the intake with a clean rag on the screen exiting the airbox and was able to successfully complete the IAVL process. The problem being this is an artificial way to drop the rpm, but it told me why it was not working. I pulled the old throttle body out of the trash, cleaned it up, and reinstalled. I got through the learning process the first try. So, Amazon is now sending a replacement and I will cross my fingers that the old throttle body works until the new one arrives and that the new one works correctly.
Just clarification, this being the third Pathfinder, the other two are in the past. I have not owned more than one at a time, though I am definitely a fan of Nissan products having also owned a Frontier pickup in the past.
Just clarification, this being the third Pathfinder, the other two are in the past. I have not owned more than one at a time, though I am definitely a fan of Nissan products having also owned a Frontier pickup in the past.
Re: Idle Air Volume Learn Fails
I just thought I would follow up. I received the replacement part, installed it and used the Data Scan software to perform the Idle Air Volume Learn and it work without a hitch. I spent a lot of time diagnosing the issue that ended up being a fault new part.
Re: Idle Air Volume Learn Fails
Hey Tedr, could you tell me or pm me where you got the data scan software?Thanks.