Stone27

I just got a 09 G37x 7-speed auto with 93k miles on it. Car was a one owner that appears to be near flawless condition and very well maintained. A little less then a month after purchase I get in, start it and it dies instantly. Try again (about 3 times or so) same thing. Engine turns over then shuts off right away. Had things to do and it was late, so I let it sit over night and came back the next day with the plan to tow it to the dealer. Got in the car n now it starts right up n keeps running (normally) only the SES light comes on. I went to autozone to have the code checked and it comes back one code P2103 indicating a faulty Throttle control motor relay or a short circuit in that system or poor connection within that system. I would love to just replace the relay (should be easy, quick and cheap) but I can't seem to find any info as to where it may be located. Scouring the internet for this code brought up ZERO and a little less then a week later the SES light disappeared. I thought it might have been some minor glitch or something. Now a week a later I get in the car in the morning and it happens again. This time I need to get to work so I tried to reset the ECU (successfully) but still starts and dies instantly. I decide to unplug the negative battery cable for a minute and plug back in, which worked and now here I am. I know this issue is not gone forever it may happen in a couple hours on my way to lunch. Any information on a possible fix (preferably a DIY, I don't have a few thousand dollars to go to the dealer and I am mechanically inclined) for the P2103 code would be very much appreciated. Also I need to know if the code showing is the cause of the no start condition or a separate issue altogether.

ANMVQ

iTrader: (13)

The actuator is on the TB, I think this was the same code that was on the ported TB's thread if this was damaged in shipping? look for the that thread

SonicVQ

Welcome to the forum!

P2103: Throttle control motor relay circuit short
Keep in mind, trouble codes are really the symptom and not the cause. A P0xxx does not mean "replace xxx".
It is always best to troubleshoot and verify the problem.

I think you have one problem.
If the throttle body can not be verified to be in the correct position, the ECU will kill the ignition and starter.

Questions:
(1) How old is your battery?
(2) Does it have any aftermarket stereos / alarms / other stuff wired in?

I would:
(1) Measure the voltage of the battery after the car has sat all night. It should be 12.5-12.6ish volts if the battery has 80-90% of full charge. If it is less, a low battery could be the issue.

(2) Look at the factory service manual (Infiniti G35 / G37 Factory Service Manuals - NICOclub) for your year and follow the procedure to troubleshoot P2103. (EC-438 for my 2011)

Stone27

Car is completely stock no mods or any additional accessories. I'm not sure how old the battery is, but when it first happened that was first thing I checked but it was fine when I put the meter on it. Though I did have the car running just 30 min before it wouldn't start and I checked the battery so I will check again tomorrow morning as you suggested. BIG THANK YOU for the link, I'm all over that now and confident I'll figure it out.

Stone27

For the rest of the day (yesterday) I had to keep unhooking the negative battery cable to get the car to start up. Battery checked out fine this morning and on top of that the car started right up without needing to disconnect negative cable. I did locate the troubleshooting procedure in the FSM. I'll check it out saturday morning and post results.

SonicVQ

Just curious, what was the battery voltage?
Good luck!

Stone27

sorry about late reply, lent multi meter to my friend the first time I checked the battery (and couldn't remember the reading). Anyway I've since got it back and the reading was 12.18 this morning. It has been turning on without fail since my last post though I still have the P2103 code so I do believe that it was a unrelated issue. In any case I haven't gotten around to fixing yet as this car is new to me so I find myself looking around the net forever for the smallest explanation for things.

SonicVQ

FYI: 12.2 volts is about 60% charged. That is a little low.

If possible go for a 1-2 hour drive and check the battery voltage in the morning. If it is the same, your battery may need to be replaced soon. If it is 12.6 or more it is now at 90% charged and shows the battery can receive and hold a charge.

CCM

Hi, I have had the P2103 code thrown 2010 g37x. I do have a dash cam hardwired to the car. How might this be causing the code? What should I do? Just clear the code? Car seems to be running fine, but have SES light on. Thanks.