Hey, The check engine light came on in my 03 RGR. I went to Auto Zone and Advance today and neither could get there code reader to pull the codes off my truck. They would plug it in and nothing would happen. Any advice?

 

It is possible that the plug in the vehicle, which provides power to the scan tool might be malfunctioning, however, there is also another reason why you CAN NOT pull codes:Your PCM (computer) contains programs that are used as a back up when you have a sensor fail and it cannot signal the computer, and this allows you to drive you vehicle, but the sensor that is out is replaced with a fixed value in the computer so your engine will continue to operate-however it will operate with performance and drivability issues. This is called FMEM, or Failure Mode Effects Management.. If a fault is too extreme for FMEM to handle, HLOS, or Hardware Limited Operation Strategy kicks in, and the PCM has stopped ALL computation and control, and the entire system (all your sensor readings) are set at a FIXED value, and the vehicle will run, but performance and drivability will be greatly reduced..This allows the vehicle to be driven in for service, AND NO CODES CAN BE READ WHILE THE SYSTEM IS IN THIS MODE!!! Not meant to scare you, but I read this in my Chiltons manual..I don't have any idea how your truck is running, or how it drives, but I'll tell this , if it IS in this mode, driving it can not be good..I hope it is the first thing I mentioned-Good Luck......

 

Is your cigarette lighter working?

 

No it is not. I checked it and replaced it today. Is this the cause? I will take it to Auto Zone tomorrow and check it again. Thanks

 

What XLT is getting at is your vehicle is not allowing electrical power to places that should have power, like your cigarette lighter, and we know your scan tool wasn't getting its needed power either...Possible problem in the fuse boxes, either in the cab, or under the hood in the Power Dist. Box...Need to check it out!!

 

The scan tool plugs into the data link connector & the data link connector & the cigarette lighter are both wired to the same fuse.

If that fuse is blown.......

 

Sorry I miswrote my earlier reply. I replaced the fuse for my cigarette lighter and will take it to Auot Zone today.

 

Nice thread guys. I tried to pull codes from my father-in-laws 99 ranger today and got nuttin. Ive been searching this site for hours before I ran into this. I knew my scanner was working because I pulled codes from his Olds Achiva. He had to leave for the day, but I called him and he said his lighter is not working. Tuesday is the first time I will have chance to look at it again. Thanks for the help. I'll try to post the result in a few days.