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what's this wire for?

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Monkeydonkeyratmagic
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what's this wire for?

Post by Monkeydonkeyratmagic » Tue Oct 31, 2017 3:39 pm

So cleaned put the filthy carpet behind the passenger seat and noticed this wire hanging off.

Everything on the car works, all seat adjustments and heater. It doesn't seem to go anywhere that has connection and the wire is flat cut off. No prongs or wore excess at all.
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Anmarube
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what's this wire for?

Post by Anmarube » Tue Oct 31, 2017 9:53 pm

It's part of the seat lining that goes around the frame..Not a wire at all so no worries on that front..

Ooooops, Did'nt notice the blue wire behind the white one..

Apologies
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Monkeydonkeyratmagic
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what's this wire for?

Post by Monkeydonkeyratmagic » Thu Nov 02, 2017 4:54 pm

Surprised no one seems to know what the blue and white wire are for. Be interesting to know.
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Mike6
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what's this wire for?

Post by Mike6 » Thu Nov 02, 2017 5:04 pm

Ejector seat electrics??. Possibly some sort of extra added by previous owner.

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MACK
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what's this wire for?

Post by MACK » Tue Nov 07, 2017 3:19 pm

It looks like the wiring for the passenger seat occupancy sensor and its control unit. Unless you have the warning light on the dash my guess would be someone has done the bypass mod either because the seats are original and the mat was playing up. Or you have facelift seats in a pre facelift car and some folks have had compatibility issues (myself included) so have modded the wiring . Not really heard of any issues with seat occupancy mats in the zed. However it's common in most other Ex BMW models so I would not be surprised if thry are original seats and it had failed.
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Monkeydonkeyratmagic
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what's this wire for?

Post by Monkeydonkeyratmagic » Tue Nov 07, 2017 3:45 pm

MACK wrote: Tue Nov 07, 2017 3:19 pm It looks like the wiring for the passenger seat occupancy sensor and its control unit. Unless you have the warning light on the dash my guess would be someone has done the bypass mod either because the seats are original and the mat was playing up. Or you have facelift seats in a pre facelift car and some folks have had compatibility issues (myself included) so have modded the wiring . Not really heard of any issues with seat occupancy mats in the zed. However it's common in most other Ex BMW models so I would not be surprised if thry are original seats and it had failed.
I do in fact have an airbag light on at the moment, guessing this is why. I did move the seat to the highest point to clean the carpets and that's when I found it. The light came on the following day.

With this new information that I clearly omitted from my OP. Any idea which part it would go into? I doesn't have any connectors attached and would the light go off if reconnected or is a OBD reset job after?
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what's this wire for?

Post by MACK » Tue Nov 07, 2017 3:56 pm

There's a little black box under the seat on pre facelift cars. If you Google e46 seat occupancy sensor you'll see the little black box. Repair wise it depends where exactly you have severed it. If you managed to pull it out of the seat mat itself or the wiring plug at the control unit you'd be best doing the bypass mod. If you broken the wiring mid wire you should be able to reattach the wires to each other. Looking at your pic though i think it looks more likely youve pulled it out of the mat or controller plug unfortunately. It actually looks like the wires been cut in the pic. Not sure how you manage that!
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what's this wire for?

Post by Monkeydonkeyratmagic » Tue Nov 07, 2017 4:10 pm

Right, Cool, This is going to be fun. Going to head out and take a look underneath it now and see what's what. I thought it was for the Bosch unit visible in the photo with a wire missing but a plug visible but it doesn't seem to reach. Will update shortly.
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what's this wire for?

Post by ph001 » Tue Nov 07, 2017 4:38 pm

That 'Bosch unit' is the motor for the seats.
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what's this wire for?

Post by Monkeydonkeyratmagic » Tue Nov 07, 2017 4:51 pm

right so it seems that box only has 1 set of blue & white wires going into it. explains the wire sleeve on the floor also as it's that wire that's come out.

Does this module just unclip from the seat I take it? I'll give it a go soldering it back in before spending a whole £10 + Reset fee on it 1st.
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what's this wire for?

Post by MACK » Tue Nov 07, 2017 5:03 pm

Monkeydonkeyratmagic wrote: Tue Nov 07, 2017 4:51 pm right so it seems that box only has 1 set of blue & white wires going into it. explains the wire sleeve on the floor also as it's that wire that's come out.

Does this module just unclip from the seat I take it? I'll give it a go soldering it back in before spending a whole £10 + Reset fee on it 1st.
IIRC you dont need to have a reset on this, just turning the car on and off is enough for the seat occupancy system. so a bit of time hassle and money saved there then. yes the box does just unclip, in fact the seat comes out in 5 minutes, its only 4 16mm bolts I think. Might make things easier
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what's this wire for?

Post by Monkeydonkeyratmagic » Wed Nov 08, 2017 11:12 am

Right so, after some serious swearing at the car last night I got the box out, no clue how the wire came out but it wasn't repairable at 1st, so I split the plug open (yay for BMW using stupidly soft plastic on this) soldered it back in place and tested and boom light off on start up and it's stayed off this morning. All stupidly thin and fragile wires for this unit and now sitting nice and safe inside a layer of leccy tape and then an outer layer shrink tubing over the top and safely secured to the seat with no hanging or snag points at all.

Bypass module would have been like £10 and 20 mins of my time.

My repair job, probably about a few £ worth of materials and electric and 4hrs labour, a banged head (didn't do the windows down) and a lot of anger.
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what's this wire for?

Post by ph001 » Wed Nov 08, 2017 12:24 pm

:thumbsup:
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what's this wire for?

Post by MACK » Wed Nov 08, 2017 5:46 pm

Monkeydonkeyratmagic wrote: Wed Nov 08, 2017 11:12 am Right so, after some serious swearing at the car last night I got the box out, no clue how the wire came out but it wasn't repairable at 1st, so I split the plug open (yay for BMW using stupidly soft plastic on this) soldered it back in place and tested and boom light off on start up and it's stayed off this morning. All stupidly thin and fragile wires for this unit and now sitting nice and safe inside a layer of leccy tape and then an outer layer shrink tubing over the top and safely secured to the seat with no hanging or snag points at all.

Bypass module would have been like £10 and 20 mins of my time.

My repair job, probably about a few £ worth of materials and electric and 4hrs labour, a banged head (didn't do the windows down) and a lot of anger.
Glad you got it sorted!
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