K12 BCM removal

Hi,

newbie to this forum so please be gentle 😀
Have a micra c+c which has decided to control the hazard lights by itself, spoooky. They come on by themselves when driving and cannot be switched off using the switch. Have accessed the switch itself and disconnected it, no difference, searched the forum and the finger points to the BCM, did think it could be a faulty relay but from what I have read it’s within the BCM.
Having done some research used BCM can be bought fairly cheaply but will need to be re-coded from the original unit or company BBA Reman can repair original units. So to the challenge where is the BCM and how do you remove it ? Read that it’s behind centre console, have removed radio and no joy.

Any advice is most welcome 🙏

thanks
 
Quick update

thanks to the kind man at jcc cars who explained all. The BCM is located under the top of the dashboard passenger side, to access you have to remove the A pillar covers on both sides of the car, found I had to take the sun blinds off as well, the screws hold the upper trim in place. The A pillar covers are on poppers, once they are off you need to prise the dashboard cover off, there is a small gap running round it, again poppers are used, fairly easy to get off. Then all is revealed, the BCM is held in a’cradle’ just push the BCM towards the windscreen and it should pop out, from there you can disconnect it.
On mine I disconnected and check all connections were ok and re connected and like magic hazard lights are working correctly, for now, will give it a few days and see how it goes before I put all the trim back on.
 
Possibly the center console you are looking for is not in the dash but in the center of vehicle.
Removal goes two screws at the rear each side as far as I can recall.
And two or maybe three pop clips at front the cc may differ slightly.
You have to remove this top cover to access the gear shifter mech that's what I was changing.
And I think the box with orange sticker on is the BCM aka (body control module) This also controls "airbags"ect.
Important info (So give someone a chance to let you know how to remove the item safely.)
As it's not something I have done before but am sure that's where the item is hidden.
Good luck with replacement/solving the problem you are encountering.
Hi Sparky2018
From my latest post I found it, where there’s a will there’s a way, think Will was the guy at Jcc cars.
 
The electronic side can be problematic with k12 and it's good to hear you have solved the problem.

Ps. My post was being edited and will be deleted shortly.
 
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I had a similar problem on my K12 CC - I too thought it was BCM related, turns out it was water ingress on the Alarm connector in RH side of the spare wheel well! - check it's dry. I have discovered after it has been raining, when I lift the boot lid up a load of water runs off of the right hand side and right onto the alarm connector - not sure if it's a design fault, or I have a issue somewhere. worth checking the Alarm multi-connector anyway, as it's in an easy place to get wet, as like I said rainwater can drip onto it when lifting the boot lid.
 
Could be the boot seals or just the winter setting in.
I had the door seals frozen a few week ago and since I dryed them out thoroughly then aired the cabin out well it has not happen since.
Possible fix would be an extra layer of sealing this is something I was looking at for the door seals as draft at the lower of door I noticed this when it was snowing and it could cause issues.
 
I had a similar problem on my K12 CC - I too thought it was BCM related, turns out it was water ingress on the Alarm connector in RH side of the spare wheel well! - check it's dry. I have discovered after it has been raining, when I lift the boot lid up a load of water runs off of the right hand side and right onto the alarm connector - not sure if it's a design fault, or I have a issue somewhere. worth checking the Alarm multi-connector anyway, as it's in an easy place to get wet, as like I said rainwater can drip onto it when lifting the boot lid.
Where exactly is the connector? Have noticed water coming out of the boot lid. My fix only worked for about an hour then it started doing it again, fingers crossed your suggestion is correct
 
Remove the spare wheel + tool holder & it's easy so see/access - it's on the right-hand side of the wheel well at the back. It's only a short tail - the connector is right next to the alarm module. I dried mine out by disconnecting it & putting a fan heater on it for a while. I've actually left mine disconnected - doesn't seem to affect anything else, Hazards/NATS immobiliser etc.

My symptom was the immobiliser got stuck on & the red light was flashing aswel as the Hazards. I thought the Alarm & immobiliser were separate systems on these?, but drying the connector out & unplugging it seems to have cured it - no immobiliser issues since. Even if they are separate to each other I suppose water in the connector could have caused a funny in the BCM.

Oh I also had the NATS error fault code P1611 I had to clear as well with NDSII or a code reader - So may be worth reading your DTC's & clearing them if you can

P.S. - wear a pair of ear defenders when you unplug the alarm connector! - if the internal battery is ok it will go off & it's bloody loud when your head is right in the boot!
 
Well, had my own private swimming pool in the boot, found the connector and it was under water ☔️, disconnected it (no noise from siren, battery flat ?) connected battery and all is well again for now. Is it the boot seal that is failing and is there a cure ?

thanks for the help, much appreciated 👍
 
Not sure about the water - it's not actually leaking in, so not the seals etc - it seems to collect somewhere inside the lid & drips down on the right hand side of the boot lid when you open the boot - well that's what mine does anyway.

you will probably have a fault code on the ECU aswel that is worth clearing P1611 NATS error

Glad you got it sorted - I'm so glad I checked this! - I was about to remove & strip down the body control module
 
Not sure about the water - it's not actually leaking in, so not the seals etc - it seems to collect somewhere inside the lid & drips down on the right hand side of the boot lid when you open the boot - well that's what mine does anyway.

you will probably have a fault code on the ECU aswel that is worth clearing P1611 NATS error

Glad you got it sorted - I'm so glad I checked this! - I was about to remove & strip down the body control module
 
Mine does the same, was thinking maybe the number plate holes if there rusted a bit, can’t think of anywhere else it can get in 🤔.

hazard lights are still ok 👍
 
Did some more digging on the leak, seems a few people have reported problems with the seal round the rear right light cluster. Checked mine and the foam seal is in a sorry state plus I noticed that taking out the two screws that hold it in place that there should be a popper to hold the other side in place, this was missing. Which means the cluster is not going to pull down flush on the foam seal when you tighten the screws up.
My planned fix is to get a new popper plus put a ring of silicone sealer on the car round the light cluster hole, after letting this dry first it should provide a better seal. One other tip I read was to smear to foam seal in Vaseline again to help provide a better seal.

open to other suggestions?
 
Hi everyone,
This has been informative and gives me something to go and look at but in the meantime here is my problem...

For a while we have had an alarm issue which I have narrowed down to the bonnet (engine cover) microswitch. Open bonnet = alarm sounding. A Tywrap on that has sorted it.
This week the wife has reported the hazard warning lights flashing constantly. She had to leave the car parked up and let the battery go flat and use my car as I was working away. We now have the car running and the hazards always flashing. My Tywrap is still in place but occasionally the alarm sounds as well. Water in the spare wheel well is where I'll look first for that one.

Where is the flasher relay? I have the lower console on the drivers side in pieces and have dismounted the fuse panel and can't see it anywhere.
 
From my research on random flashing hazard lights there is no relay there controlled by the BCM which if goes faulty can be expensive to fix, luckily on mine it was a leaky tail light cluster which drips water onto the connector for the alarm siren. As others have done I just disconnected the siren and taped the connector, all is working fine.
 
Well... and it seems the spare wheel well really was a well !! Damn there was almost a lake in there. That's that mopped out and the alarm cable tywrapped up in a better place.

After careful deconstruction of the cockpit trim I got access to the BCM module and unplugged it. Flashers stopped. Thank you so much for this thread, I was starting to get quite frustrated until I found it.

Now, what's the score with the BCM module? Straight replacement...? Or a recoding etc etc ? Nissan or a 3rd party?

Any help and advice about that would be great. I'm in Norwich, UK FYI.
 
Just double check the cable connector in the boot is dry and no short. As you have found out locating the BCM is a challenge but not so bad once you know where it is 🤔. One other thing to try is disconnecting the battery for a couple of hours to allow all systems to reset (have you got radio code). Regards the BCM the main option is get a unit of eBay (make sure part numbers are the same) and then you have to send both units away for the codes to be copied from old unit to the ‘new’ one. Or there is a company called bba reman who can repair them, costs about £40 for eBay unit and about £100 for re code. Believe brand new ones are £300 to £400 pounds. In majority of cases it’s a wiring problem.
 
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