I'm creating this topic as a follow-up to this thread http://forums.maxima.org/5th-generat...n-picture.html since its a different issue.

The CEL was lit on my 2003 SE and I was pulling codes P0420 and P0340. The P0420 had been there for a couple months but the P0340 was new so I replaced the camshaft position sensor and a week later (today) the CEL went away. I was expecting the P0340 to go away but the CEL to stay on for the P0420 but the CEL went away altogether. I plugged in OBD reader just to make sure and OBD reader is still showing P0420 and P0340 codes are "current", not "pending". My question is, why is the OBD reader pulling current codes when the CEL is not on?

 

When you turn the power on, does the CEL light up along with the other cluster lights before you start the car? If not, maybe the bulb went, and that's why you don't see it lit.

 

Good point. The CEL light does come on when I turn the ignition on so I know the bulb is working.

 

ok, My girlfriends Maxima had that same issue, so thats the first thing that came to mind.

 

Does your code reader differentiate between pending codes and live codes? I use the ELM 327 setup with the Torque app on my phone and it will tell you if its a pending codes versus a "live" code. Also, if you had cleared the codes using the reader, the car has to run through a few drive cycles before a permanent code might pop up and might show as pending until the car completes the drive cycles. If this is the case, it will show up in the reader, but the light will not be on.

 

Yes it does. These are "current" codes I'm pulling, not "pending".

 

What kind of reader are you using? Could be a problem with the reader. I've had the opposite issue where the CEL will be on and the code reader says there are no codes.

 

I'm using an ELM327 with the TorquePro app. Have used it several times w/out any issues. This is the first time something like this has happened.

 

The CEL came back on today with the same two codes. Very odd that the codes were there yesterday but no light. In any case, I cleared the codes and will see what happens.