[dancing__narwhal]

So I just swapped my LCI non-sport seats for pre-LCI sport seats. I've got power and memory working, but I have an airbag light and seatbelt light on my dash. I know the pre-LCI seats do not have active headrests, so is that the cause of the airbag light? What about the seatbelt light? Is there anyway to get the car to recognize that I'm buckled?

Yes, I know I can code these out but I just want to ensure all safety features are working first (e.g. Side curtain airbags in seat).

I've searched around but haven't found any specifics on these two issues.

[matteblue3er]

Did you disconnect the battery before unplugging the airbag modules? If not, faults will store.

If you're missing the airbag because it's a different design, you need to code them out.

[dancing__narwhal]

Originally Posted by matteblue3er

Did you disconnect the battery before unplugging the airbag modules? If not, faults will store.

If you're missing the airbag because it's a different design, you need to code them out.

I did not

I took my car to my local indie shop on Monday (for a different reason). They cleared the faults and they said only the active headrest fault came back (MRS).

Still doesn't explain the seatbelt warning light though...

[1QuikWS6]

The airbag fault is definitely for the headrests - you had AHR headrests, then replaced with non AHR

You have (2) options to correct this:

#1 Keep the non AHR headrests & code them out as follows - however this is obviously defeating a nice safety feature

Check out this thread: Post #6 http://www.e90post.com/forums/showth...ghlight=active

It is the ABG module. Read it with NCS expert save an original copy. Then modify the two line items

AKS_LINKS_1_CD
AKS_RECHTS_1_CD

to "nicht_aktiv"

then write the new modified file with ncs expert to your ABG module and you should be good to go.

#2 Remove the non AHR headrests and install your original AHR headrests. The car wiring harness will still have the connector so it would be PnP. AFAIK (at least with an E92) the headrests have same mounting & will slide right in to your new seats - it's the guts of the headrest that is different)

Of course, this will work easier if new seats are same color If not, you CAN remove the headrest covers from your new seats and install them on the old ones (at least I know they are the same on E92) you should be able to tell if they will swap by just comparing the covers.


As far as the seatbelt warning goes - check to make sure that neither of the inner side belt mechanisms have been deployed - if it has, you will need to replace the bad one with a new one - you can simply swap your old good belts over to the new seats. Could also be cut wires/bad connector/etc.

Easiest way to check would be to simply swap over both your old seatbelt mechanisms to the new seats since you knew they were good...

DON'T FORGET to disconnect your battery & wait approx. 15min BEFORE you disconnect any wiring for these operations

[dancing__narwhal]

Thanks for the tips! I'm going to code out the active headrests.

As far as the seatbelt, what do you mean about it being deployed? What should I look for?

Also if it's just a wiring issue, is there somewhere I can reference the correct wiring?

[1QuikWS6]

Shown below is an inner seatbelt receptacle from an E92. It bolts to the lower side of the seat mechanism. The section on the right with the receptacle arm & the accordion rubber cover is what you need to look at.

In an accident the lower metal part auto triggers a cable to 'pull' the accordion section down - tightening the belt around your body. It's a one time event so once it has been deployed you will get error messages as it is no longer functional as it should be for safety (accordion section does not return to it's original position). That pic shows section in question in 'normal' extended state - when it has been deployed that section will be collapsed.

The trigger wire for the receptacle is shown (Gray connector). that wire/connector runs under seat and is inserted in the large modular main electrical connector shell that all the car harness wires from under the carpet plug in to. If that wire is damaged, or the gray connector with contact pins inside is damaged - that may also show an error. So follow that wire under the seat & make sure it is not cut

I've seen seats where someone has opened up that main connector, slid out all the individual connectors, & put them back in such a way that the belt connector/pins get's damaged (in fact, the M3 seat set I bought had one damaged in just this way). To correct I simply swapped over my complete belt mechanism as shown in pic that were in perfect condition...

The very same threads that detail seat swaps show the main seat electrical shell w/individual connectors from seat components so you can see what I'm talking about (2nd pic)

[dancing__narwhal]

Originally Posted by 1QuikWS6

In an accident the lower metal part auto triggers a cable to 'pull' the accordion section down - tightening the belt around your body. It's a one time event so once it has been deployed you will get error messages as it is no longer functional as it should be for safety (accordion section does not return to it's original position). That pic shows section in question in 'normal' extended state - when it has been deployed that section will be collapsed.

Thanks. I checked this and it appears to be in its normal state. I did not have a chance to unbolt the seat and check the wire but I didn't notice anything wrong with the wire when I first installed them.

Should the pre-LCI and LCI seatbelt mechanism be the same?

[dancing__narwhal]

So I just tried unbuckling while driving (don't worry I was in a parking lot) and it did in fact trigger the seatbelt chime. So it seems the seat does know I'm buckled.

Why then does it give me a seatbelt warning light on the dash even when I'm buckled?

[NYBulldog]

I simply switched seat belt receivers, seats and coded out the active headrests.

If the seatbelt warning light is likely an error code. Were those seats out of a vehicle in an accident? Remember there is also the lower pad sensor for occupancy that could be faulty.

[bsmoov]

Those were my old seats.

Seat belts were not deployed, nor any airbags.

Car was rear ended in an accident, but nothing out of the ordinary.

I actually drove the car for a while with the damage with no error lights.

I have a feeling it's the passenger occupancy mat sensor...you can code that out as well.

[McPikie]

More likely to be the belt receiver. Swap the ones off your old seats

[dancing__narwhal]

Originally Posted by bsmoov

Those were my old seats.

Seat belts were not deployed, nor any airbags.

Car was rear ended in an accident, but nothing out of the ordinary.

I actually drove the car for a while with the damage with no error lights.

I have a feeling it's the passenger occupancy mat sensor...you can code that out as well.

Thanks man. Seats a great by the way. SO much better than the stock ones in both comfort and support, not to mention holding me in place when I take the turns a little too fast

I've already ordered coding from Alpine so hopefully that resolves all this. Occupancy may sensor would make sense, especially since there were a few other wires in the harness that didn't quite match up.

[bsmoov]

Yeah, once you go sport seats, you can't go back.

Luckily my new 330i has sport seats too or else I would've kept those seats.

You should've went with bimmergeeks here for remote coding, they do an outstanding job!!! Remotely, for stupid cheap!!!

[.RJ]

Did you ever sort out your seatbelt light?

I just swapped in a set of non-LCI seats to my LCI E91... havent read the codes yet though.

[.RJ]

Found this thread that has all of the info - http://www.e90post.com/forums/showthread.php?t=1230144

Pretty straightforward, but, has anyone dug into WHY the seat mat occupancy sensor doesnt work? In theory, its a simple device and the output of the sensor should just be sending a yes/no signal back to the ECU. Has anyone that has swapped non-LCI seats into an LCI tried swapping the sensor box under the seat?

Edit: I think from what I'm digging into, you can code it to the car. Looks like new sensors require this. I must be the only person trying to turn this thing on, rather than disable it. I'm guessing typically only dealers do this as part of a recall or warranty replacement, everyone else is just trying to turn them off when they fail.

[.RJ]

And, to reach closure on this for anyone interested, you can pair the new seat occupancy sensor to the car. No need to disable it, although that may be easier or preferred.

And, you dont have to disable the active headrests, either, if you dont want - you can swap them - thats what I did. There's a video here:

Its not that difficult just some time and zip ties. If you have an interior trim removal kit you can pop the seat back retainers off and re-use them, as well.

[fravel]

Originally Posted by N52 E90

I did not

I took my car to my local indie shop on Monday (for a different reason). They cleared the faults and they said only the active headrest fault came back (MRS).

Still doesn't explain the seatbelt warning light though...

Seatbelt warning light comes on with the airbag light - why? Not sure, but once you fix the airbag issue the seatbelt light should go away too.

[.RJ]

Originally Posted by fravel

Seatbelt warning light comes on with the airbag light - why? Not sure, but once you fix the airbag issue the seatbelt light should go away too.

It does not.

The occupancy mat sensors are different sport/non-sport. New one has to be coded to the car, or disabled along with the seatbelt warning.

[fravel]

Originally Posted by .RJ

It does not.

The occupancy mat sensors are different sport/non-sport. New one has to be coded to the car, or disabled along with the seatbelt warning.

Yes it does. My drivers seat side airbag went bad in my car and it gave me the airbag warning light, the seatbelt light and the little dude with a balloon on his lap in the CB readout. Once I replaced the airbag and cleared the code all three went away.

I'm not sure what light would be triggered by bad seat mat sensor, but my point is that the seatbelt light in conjunction with the airbag light does not necessarily indicate an additional problem to the known issue described by the OP of not having the headrest restraint system hooked up.

I'm also not sure you're correct about having to code the seatmat sensor to the car. When I swapped my non-sport with sport seats (Pre-LCI to Pre-LCI) it was plug and play, I didn't have to code anything.

[.RJ]

Originally Posted by fravel

I'm also not sure you're correct about having to code the seatmat sensor to the car. When I swapped my non-sport with sport seats (Pre-LCI to Pre-LCI) it was plug and play, I didn't have to code anything.

Weird. I've read about several others having the same issue with the code for the seat occupancy sensor, and mine had the same. I'm surprised yours was plug & play. I guess its not as certain as I thought, then, when swapping to the sport seats. The tech I bought my seats from said the part # was the same across all years, so it didnt change with the switch to LCI. Good data point.

[6ixSpd]

I know OP probably has figured it out by now, but ANY fault in the SRS system triggers the airbag lights. Any fault in the restraint system (ie. AHR equipped car using non-AHR headrests) will trigger a seat belt warning light as well. That light encompasses anything in the restraint system, it's not only for buckling your seat belt.

[Adieu]

Resistor trick for the AHR (explosive headrest) clip

AND you STILL need to clear the light with a scanner capable of resetting SRS codes even after it detects the fix (clearing without a resistor won't do shit though, you gotta do both)

Cheapest scanner capable of clearing SRS faults on bimmers was the C110+ when I looked into it ... costs about $43 on amazon