Hey Everyone,

I own a 2012 Infiniti G37 Coupe Auto and have the yellow key light on AGAIN. Before, when it was on, I went through hell and back a few times as each time it was a different issue, and now I am at my wits' end and don't know what it could be this time.

Any help would be super appreciated and I would love it if someone could please help me out, it feels like I am chasing ghosts.


I am going to try and give a lot of context and will try to provide a TLDR at the end.


- September 2023: Bought the car; it had an aftermarket remote start system installed that didn't work. I never cared much about it, so didn't ever get it fixed.

- I also got sunroof drains cleaned first thing since I knew these could lead to big issues in car later on down the line.


- October 2024: I get no start, no crank issues, goes away every few days after disconnecting the battery and then just doesn't go away randomly.

- Replace battery terminals, key fob battery, and positive battery fuses and nothing works, give up and let car sit for 1 month as I focus on college finals.

- After finals are over, about to get it towed to a mechanic when it randomly starts up (using jumper cables), go to a few shops and figure out it could be because of the old remote start, get that module fixed and now I have working remote start plus no yellow key sign.

- Car is working fine and great and never have any repeated issues for a few months.


-2025 April: Parking up at a restaurant and put the footbrake on and notice yellow key sign is on when I put the footbrake on.

- Look under driver steering column as that is where remote start was wired, but yellow key sign dissapears in a few minutes on its own.

- No worries again, just a scare.


- 2025 July: Have heavy flooding level rains in area and day after car won't start and won't crank.

- Notice BCM got soaked somehow even though sunroof drain had not given me issues before (Could it have came in from the bottom somehow?).

- Dry BCM using heat gun and taking it out.

- Car is working again and I am not worried about the BCM.


- 2025 September: Going for a job interview and car doesn't start and leaves me stranded, yellow key sign on, randomly disappears after a day and a jump start.

- Notice water on driver side, passenger side dry.

- Decide I am now going to permanently reroute sunroof drains just in case of any issues in future.

- Reroute goes well, pull all carpets as well and car is dry.

- I also hose down the firwall and the door seals thinking let me make sure these are not the reason I have water inside my car as well.

- Leave car in driveway for a week, parked, just to ensure that sunroof reroute worked. (Had 3 different rains this week and both sides were dry after the rain).


- 2025 December: Driving home after the gym (Was in sauna with car keys in my pocket, idk if that matters), hit a pothole and yellow key sign comes back on.

- Make it home and turn car off, again no start/no crank.

- Firstly, get remote start system removed because I think this is the root cause.

- Doesn't work.

- Check: Brake position sensor, Neutral lockout, all fuses related to ignition, battery terminals, positive battery fuses, and get the car's battery health checked and it comes back as good once fully charged.

- Doesn't work.

- Get my friends body scan tool and BCM returns 12 codes.

- Figure that the time a few months ago when it got soaked finally did its number, and I guess the pothole finalized it.

- Find a replacement used BCM with matching serial codes and get it programmed to the car.

- All good now.


- 2026 February: Within 500 miles of getting new BCM in, I noticed that one time when I put the foot brake on, i saw the yellow key sign come on for a split second.

- Disappeared right away so no big deal.

- Also, notice that there is water underneath the driver's side rubber weather mat that I have. It came after I first drove my car after getting it back, after a snow storm but roads were dry and my heat was on all day in the car.

- Where could it come from if it is not sunroof drains and I sprayed door seals and firewall to make sure they don't leak?

- Anyways, no big deal, I will get around to it once weather is nicer since it was close to the acceleration pedal and no way this would damage any of the fuses in kick panel.

- Go snowboarding, car key has some moisture on it, dry it all off before getting back in the car.

- Car starts up fine, on the way home now.

- Stop on the side of the road and put parking brake on and yellow key sign comes on again and stays solid whole drive back.

- Out of fear I don't turn car off until I get home, once I am home and put the parking brake on again, the yellow key sign dissapears randomly.

- I start it up one more time and it works and I feel satisfaction it dissappeared.

- One hour later I go out and notice again, the yellow key light is on and there is no crank when the car is in the on position.

- Don't know what it could be at this point.


Thats the whole timeline of this issue with the car and I am honestly at a loss for words because either I am the worlds most unluckiest G37 owner, or I am just cursed. Either option seems feasible.

I currently have my key in rice to let it dry even though it already was dry. I don't know what to even look for now on the car, I looked at the BCM and it is completely dry and there is no moisture around it either.

This can't be the steering lock as my car doesn't have the fuse in place for the steering lock and I can turn my wheel fine and don't notice any locks to the steering.

Surely not the BCM again because I just had it replaced and theres no moisture around it at all.

Could be some issue related directly to my key as it did have some moisture around it today.

Could be related to the water on the drivers side floor even after replacing sunroof drains.

Could also be related to the damn parking brake somehow, how does me engaging parking break keep on triggering this yellow key light more than one time.


Any help or guidance would be appreciated, I learned a lot from going through this issue but this is literally my only issue with my car that is recurrring and I can't seem to find a fix for it. I am so sick of this, otherwise wonderful, car at this point and feel like I hit dead ends everywhere I go.


TLDR:

Yellow key sign on and off since 2023, final fix was BCM, literally a few weeks ago, and yellow key light on again after engaging parking brake for some reason. Happened before when engaging parking brake as well. Makes a no crank no start issue. Sunroof drain re route already done and no moisture around BCM. Water on drivers side floor somehow despite sunroof reroute.