I drive a 2010 G37 & I recently replaced my Key Fob battery. Everything is working fine, However now I'm unable to open or close my vehicle manual with Key Fob in my possession (my pocket or hand). I reading that everyone is having Key Fob issues but i haven't herd this problem I'm having. I must be the only G37 owner who's having this problem because it's has never been talked about. Please help me out with this existing problem. By the way, my Key Fob was completely dead until I replace the battery. I could only open my door with the emergency Key that's provided within the Fob. Once I replaced the Battery, everything was back to normal except the mentioned issue. Looking for help. Maybe I need to reprogram my Smart Key? Who Knows? Please help.

GW

 

So, when the battery in the fob was dead, were you starting the car by putting the fob in the "port" above the driver's left knee? And are you still doing that or can you start the car with the fob in your pocket?

Even if the fob has not had a battery in it for a long time the car should remember how to communicate with it. That is IF the new battery is good, the contacts have not been corroded or bent, and you're sure it's put in correctly (+ side faces the bottom, smaller disk towards the circuit board).

 

The battery is inserted correctly. The car started even with a dead battery. I'm only having this one problem. Most owner's probably wouldn't care as long as the vehicle Fob works correctly. I would just like to open & close my doors manual with key in my possession.

GW

 

How is that possible? Does the car start for anybody who presses the brake pedal or do you need to put the fob in the "Intelligent Key port"? That's the only place that can read the key's chip without the fob being powered.

Can you lock / unlock the doors and open the trunk with the buttons on your fob, now that the battery is good?

 

Yes I can do all of that. The dead battery was the Key Fob. Sorry about that.

 

The bottom line is that my car opens/close with the FOB but when I try to lock/unlock my door with by hitting the door locks does nothing. Same thing with my trunk. This is with the Key Fob in my pocket.

 

Sorry, I'm still trying to understand... How did you start the car with no battery in the fob? If the system is working correctly, you should be able to start the car with the fob in your pocket.

The way I understand it ... there are like 3 systems at work with the iKey. #1 is the button functions on the fob; lock, unlock, trunk, and alarm, which you say are working correctly. Those actively transmit a signal from the fob which the car is listening for and tells the BCM to unlock the doors - like a garage door opener. That confirms that the car recognizes your fob's code and that should mean that the fob is correctly "registered" with the BCM.

Function #2 is when you press any of the exterior "request" buttons, on either front door or next to the trunk. That causes the car to transmit a radio call to which the fob is supposed to respond to with its code. That's a lower powered transmission than the fob buttons and only works if you are standing close enough to the doors or trunk. This is the part you say is not working.

The 3rd part is the embedded chip in the mechanical key itself. If your iKey battery dies you have this backup mechanical key to open the driver's door. Then to start the car you need to put the entire fob (with mechanical key back in place) into the iKey port above the driver's left knee and the car will scan that spot looking for a registered chip.

And I presume this is what you had to do to start the car when the fob's battery was dead? And is this still what you have to do to start the car - put the fob in that port?

I would also take a look at some fuses. Specifically, #3, 4, 6, 9, 10, & 11 in the fusebox near the driver's left leg. These are all involved in iKey and BCM functions.

Somebody else in here probably understands the system better than I do but I hope this helps.

 

Function #2 is my issue. How can it be fixed? The dealership it what I'm trying to avoid.

 

How do you start your car? And have you tried the passenger door request button?

 

I never said my car doesn't start. My Key Fob works perfectly. Both passenger doors & trunk REQUEST BUTTONS aren't working with the Key Fob in my pocket. That's it in a Nut Shell!

 

OK, Copy. The car starts with the key in your pocket - as it is supposed to - but the door and trunk "request" buttons are not responding. Took me long enough.

That's a weird combination of malfunctions because when you press the "engine start" button, the car looks for the fob in the cabin in the exact same way that it is supposed to look for the fob when you press an external request button. There are two antennas in the cabin that call to the fob, the fob replies with the correctly registered code and the engine cranks. It should follow that same sequence of events when you hit any of the outside request buttons. There are antennas in both front doors and one near the trunk latch which should communicate with the fob in that same way.

I don't think the interior and exterior parts of that system are saperate so I can't figure out why "start" would be working but "unlock" would not... I'd still suggest checking the fuses I listed above, but I'd be surprised if that was the answer. Has your car ever had a remote start or aftermarket alarm? Anybody been tampering with the BCM connection? Sorry I can't do any better.

 

Here are two tests I would ask you to perform:

First, lock the car using the interior door switch and walk away for 5 minutes..

Then, leave the iKey in the house and walk up to the car. Look in the window at the gear indicator on the center console shifter- the "PRND" indicator AND your engine START button. They should be off/no lights.

Now, keeping a eye on that indicator and button, press the exterior door request switch. Does the little orange Led on the shifter light up and does the LOCK LED on the button light up? Repeat for passenger door and trunk.

Now, go, get the iKey and repeat the above test.

The BCM is what provides power to the exterior request switches AND the little antennas in the door handles and the trunk. If that little orange light does not come on, then the BCM is not monitoring those circuits. Being that it seems all three circuits are non-responsive indicates a likely issue with the BCM.

As 13_SkylineSedan suggested earlier, it would not hurt to check your fuses. Further, I would check to make sure there is no water leaking in that area as well.

 

I will check as requested. I'll let you know how I make out. Thanks!

 

Here's my update. First, I locked the car using the interior door switch and walked away for 5 minutes per request. The ikey was left in the house. The center console shifter and engine start buttons where off/no light. Next, I pressed the exterior door request switch. Yes, the little orange Led on the shifter & Lock LED buttons came on. Same for the trunk & passenger side. So, I guess the BCM is working properly. I'll check the fuses in the morning. Thanks again guys.

 

Being that those LED's illuminate indicate that the BCM is receiving the LOCK/UNLOCK request signal from the exterior door switch. Question then becomes is the BCM receiving the correct encoder signal from the fob?

Another item you can check: I know some models will allow you to enable/disable the iKey Lock/Unlock system entirely (the exterior buttons). This menu is accessed through the "Settings -> Comfort" selections on your AV unit. It is unlikely this setting changed "by itself" but stranger things can happen.

If everything else checks out than either the issue lies with the antennas or the fob.

Do you have both fobs, or just one?