Hi all. I've read the threads that discuss this particular light and followed the advice of some of the posters. Here's the complete experience so far. Just wondering if anyone has any opinions/comments or can help answer some of the questions I have.

I got 4 new tires installed (Michelin Primacy MXV4's) on late Tuesday/early Wednesday this week at a local shop (the only recommended installer on tirerack.com). I picked up the my car Wednesday afternoon and the shop owner told me that the "Service Engine Soon" light was on (solid, not blinking/flashing, and no other lights on). I've owned the car since new for almost 4 years now and have never seen this light come on. After reading some posts here I've done the following:

1. Took off my gas cap and tightened it again, 6 clicks to be thorough, on Wednesday night.
2. Drove to AutoZone and had them run their OBD scan tool to get the code. It came back as:

U1000
Manufacturer Specific DTC

3. Called my Infiniti dealer (northern Indianapolis) and asked them to look up the code. They told me it was meaningless to them as all of their codes start with "P". I later checked online for a list of OBD-II codes and found there are more than just powertrain codes available (such as BXXX Body, CXXXX Chassis, UXXXX Network). Maybe Infiniti doesn't use these other codes (http://www.obd-codes.com/trouble_codes/infiniti/ only lists powertrain codes)? Can anyone elaborate on this? They then asked me if I had gotten fuel within the past 48 hours. I stopped them short and told them I was aware of the loose gas cap causing the light to turn on and that I had removed and tightened it again. I was then told to wait 48 hours for the light to turn off. Also, they told me that this light is related only to the emissions system in the car and is in no way connected to tires (only TPMS is).

1.5 days has passed and the light is still on. I'm skeptical that it's being caused by a loose gas cap unless somehow I didn't manage to fully tighten it for the first time in almost 4 years. The car drives fine, no noticeable loss in power or anything of the sort. I'm likely going to end up taking it to the dealer to get it sorted out. If nothing ends up being wrong, should I be concerned that the monitoring system is malfunctioning? Or is it acceptable to just have the dealer shut off the light?

Thanks!

 

That's a code that can be had on many Nissan products and is not limited to the G. It doesn't seem to matter what model you have... it seems to mean the same thing. It appears to be a possible faulty harness or connection. That's the good news.
The bad news is that it seems to be related to an ECU and if it's not a simple connection issue, it may mean $$$ to repair.
I did a quick Google and found the following...

http://www.nissanhelp.com/diy/obd_co...00_nissan.html

U1000 NISSAN Description
CAN (Controller Area Network) is a serial communication line for real time application. It is an on-vehicle multiplex communication line with high data communication speed and excellent error detection ability. Many electronic control units are equipped onto a vehicle, and each control unit shares information and links with other control units during operation (not independent). In CAN communication, control units are connected with 2 communication lines (CAN H line, CAN L line) allowing a high rate of information transmission with less wiring.
Each control unit transmits/receives data but selectively reads required data only.

Symptoms
- Engine Light ON (or Service Engine Soon Warning Light)

Possible causes
- Harness or connectors (CAN communication line is open or shorted)
- Faulty Engine Control Module (ECM)

Possible solution
- Poor harness ground connection.

When is the code detected?
When ECM is not transmitting or receiving CAN communication signal of OBD (emission related diagnosis) for 2 seconds or more.

Nissan Service Bulletin in PDF form

 

Thanks for the information. I'm probably going to end up taking it to the dealer since I have some other items to discuss with them (door panel peeling trim being one). I'm hoping that no matter what problem is found, it'll still be covered under what little I have left of the manufacturer's warranty. If not, hopefully my WarrantyDirect warranty will cover it.

Thanks again for the info. Love you guys!

 

If you're under warranty, it's covered.
Just make sure you make the appt and get it in before the warranty expires.

It's good that you have the extended but don't rely on it. Get the car in now and they'll take care of you.
Good luck!

 

Oddly enough, exactly one week after the light came on, the light turned off (last night). I hadn't gotten any fuel or touched the filler cap in over 5 days.

Not sure whether to be happy or worried. Did I miss "self-healing" as an advertised feature of the G? I figure if a diagnostic check is run now, no error codes will be returned. Is it pointless to take the car into the dealer at this point (other than to fix the trim)? I'm assuming they'll claim there's nothing they can do if no errors are present.

Funny thing is, I originally had an appt at the dealer for 1pm yesterday. The door trim was on back order though so I told them to cancel my appt and call me when the trim came in. And thanks to Murphy, the light is now off. At least he didn't wait until I was on the way to the dealership.

 

I use the same dealership. Did they actually approve replacing the peeling door handle trim piece?

They wouldn't for me. I had to call Nissan corporate who gave me a $200 service credit. Then the service manager at the Indy dealership pulled me aside and said (very politely) that he took some offense to that; his business won't get paid for their labor and he felt my case was abnormal wear and tear. I said I think Nissan wants to back their choices in manufacturing and since they used a door handle material that wears out incredibly quickly, they'll stand behind replacing them and he should have approved the replacement. I told him many other dealerships replace them no questions asked.

He replied that he doesn't "fudge numbers" like that and that there is no code to replace handles under warranty.

I didn't really get it, so I guess we agreed to disagree

 

I was only told verbally over the phone that the peeling door pulls would be replaced under warranty and would include all 4 doors, to help ensure even wear in the future. They told me they've already order the trim but that it's on back order and would call me once it comes in. A lot can happen between now and then so I'm not holding my breath. I will certainly keep sending updates as I have them.

How long ago did you have the trim replaced? Perhaps they've changed their policy after getting more complaints?

 

I carried out this process 3 months ago. Yes it's quite possible they changed their process, or that the S.M. really thought my handles were some "abuse" case (I don't think they were, but that doesn't really matter).

 

I just talked to D&R service. The trim is in and my appt is for this coming Tuesday. I'll post an update afterward. They also agreed to run a diagnostic even though the service engine light turned off 2 days ago. They said sometimes the error codes are actually stored so they may be able to pull it after the fact.