Airbag seat sensor BYPASS is draining battery

[whizzkid23]

Originally Posted by jeffmiller

2006 X5 3.0 6MT

Airbag light came on, local indy shop identified it as a broken passenger seat sensor. recommended I pickup a bypass to get the airbags working again.

Purchased the bypass (which included the seatbelt sensor) from Airbag360.com. (2006 models had slightly different sensors than earlier X5s, which I learned the hard way).

installed both sensor bypass units and ended up with a dead battery the next day (Airbag light did turn off though). Jumped it and continued to have dead batteries for the following week. Had battery/alternator checked out at auto zone. Both a-ok. I removed the sensors since it's the only thing I've recently changed. Battery problems immediately stopped.

Waited a month, no battery problems, so tried installing the sensors again. Again within 24 hours the battery was dead. And continued to die for the following week.

JUST TO BE SURE, I repeated the removal/ reinstall process for a third time. Same results.

Contact to Airbag360 has not gotten anywhere. ("I'll ask technician...")

Anybody have any thoughts? My next move is to have BMW fix the seat sensor, which I hear is $1k! (also my car does NOT qualify for the seat sensor recall - it's build date is 60 days too late. Grrr.)

I have a 2006 X5 3.0i Automatic Transmission...I went trough this process I think 2 years ago.
The first module i bought, didn't drain the battery...but it made the car behave like it had electrical gremlins. For example, sometimes when we came back to our car after parking it, the hazard light were flashing without any reason. Other times right after getting out of the car, we weren't able to lock the car with the remote for about 10 minutes. The most annoying and frequent bug was: KEY IN IGNITION message when we shut down the car and opened the door, even if we had removed the key obviously....
I think i looked for the culprit for about half a year before I finally tried to unplug the seat emulator when the KEY IN IGNITION message was ringing. TADAAAA - the message disappeared immediately.
I then bought another (different type) seatmat emulator. It worked - as did the first - but 2 days later: Drained battery!
This time I was aware that the seat mat emulator could play bad jokes... again I removed it just to find out: No more battery drain.
The reason for all this is probably a lack of comunication between the seat mat emulator and the other devices of the car. Even if it makes the Airbag light disappear, it seems it seems that it's comunication is not 100% what the car asks for.
The latest X5's (as yours and mine) have had some newer type of seatmat installed.... By now and with the experience gained (as you said: the hard way) I don't think it is covered by any module available out there.

In the end i ended up using BMW Scanner to code out the OC3 system. I don't like this solution... because I can not be 100% sure what's behind this "one click" coding and if the Airbag still works. I've planned to use NCDS Expert to read how the car coding has been modified.

What I can tell you is that after disabling the OC3 system in BMW Scanner, also the Seatbelt warnings / display is disabled. Still the Airbag lights comes on for a few seconds when turning on the car (as it should), to do it's operativity self test. Same for the passenger seat airbag light on the roof.

[Overboost]

Originally Posted by whizzkid23

In the end i ended up using BMW Scanner to code out the OC3 system. I don't like this solution... because I can not be 100% sure what's behind this "one click" coding and if the Airbag still works.
What I can tell you is that after disabling the OC3 system in BMW Scanner, also the Seatbelt warnings / display is disabled. Still the Airbag lights comes on for a few seconds when turning on the car (as it should), to do it's operativity self test. Same for the passenger seat airbag light on the roof.

I would think for safety, the airbag will still be functional and will probably deploy with or without pressure on the seat. It would be a legal nightmare for BMW to have this bag not deploy because of a faulty seat mat sensor and indeed a passenger was in the seat .

[whizzkid23]

The problem mainly is that the faulty seatmat is a inconsistent problem.
The failure starts with wrongly interpreting if there is a child or a adult on the seat, that's long before the system recognizes the seatmat is faulty and definetly shuts it off by coming up with the airbag light on the dash. It's nice when you sit on the seat and somehow the "passenger airbag off" light shines at you...

In my case, I ended up coding the OC3 system (occupancy classification) with a non BMW approved tool. I doubt they will be held responsible for any damage / harm caused by that = no airbag deploying after coding out the OC3.

@Jeffmiller: If you live in USA...there should be a recall for this issue. You should get the mat replaced for free by BMW! I live in Italy...no recall

[Fifty150hs]

In the US the seat mat is a recall item. The dealer will replace it for free. Outside the US I don't think this applies.

[bcredliner]

Obviously airbag function is a critical safety item. I wouldn't do anything that you are not positive will fix your issue in a manner that the airbags functions as designed.

If you didn't start with a diagnostic tool that addresses all airbag and seatbelt codes that's the first thing I suggest you do. If you DIY a good code reader is must have item. After you installed the new parts did you clear any associated codes? https://www.youcanic.com/bmw/airbag-light-on

Since the battery drain was directly associated with the installation of new parts I suggest you then eliminate the possibility you have wrong parts, bad parts, infantile failure or that something in the installation caused the parts to fail such as shorting them out or an arc if battery was not disconnected during the repair. I would exhaust all options to get help from seller which should be the best source for a solution. Having visited the site, emulators are their primary business so you should be able to get a response based on the exact product and circumstances you are experiencing. They offer both email and phone contact. I usually get a better response from emails though when I get a response that says they will check with a tech it usually means I won't get what I need.

I wouldn't do a workaround that there is any chance at all that the airbags won't deploy properly.

[jeffmiller]

Hi gang, thought I'd follow up.

After multiple battery drains and jumps, the battery finally gave up the ghost and I had to tow to my local BMW independent specialist. They couldn't believe that the seat sensor bypass could be draining the battery, so they installed a new battery and went through the whole system.

I think you know where this story is going, it WAS the seat sensor bypass. It wouldn't let the car go into sleep mode.

Second thing I learned was that on a Manual transmission vehicle, the way to check if your car goes into Sleep Mode is to watch the glovebox light. It should go out after 15 minutes.

With a new battery, and the seat sensor bypass removed, I'm back on the road again. The vendor (Airbag 360) never got back to me, but I will be returning the module.

If I want my airbags working again, I have to take a trip to BMW and pony up $1k (my vehicle is too new for the recall). Grrr.

Thanks all for the replies!

[MillerTimeBMW]

Back to life, I'm in the same position with my E83 X3, I can't get the car to sleep without disconnecting the BUS wire from the pass seat, quite strange. Might be time for a new Emulator???

[whizzkid23]

In my mind the only clean solution is programming it out....

[X5chemist]

The first error fixed on my X5 was a failed passenger seat pad. My X5 has this one installed. No faults or codes with it. A seat extender is used to turn off the light and chime. It has worked great. Mine has a sleep problem too. The problem started months after the seat bypass was installed. The GMIII is out for repairs. Hopefully it fixes my X5 sleep issues and electrical gremlins.