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Discussion Starter · #1 ·
OK so hoping someone can help me diagnose this problem..
finally i was able to read the error code that was brining up my airbag warning light.

it is B100E, really struggled to find info about this on the net.

the text associated with the error is:
Driver's side airbag resistance
Resistance below minimum limit


Simple enough to understand.

So i tried the orange connector box below the drivers seat. disconnected, sprayed some WD40 on it, error didn't go away.
the last activity i remember having in that area was probably 1 or 2 days before when i dropped a cap in-between the drivers side seat and the centre console. so i suspect I've bumped something when i was retrieving it. so i tried to fiddle with some of the other connectors in and around that area, still no luck.

here is a screen dump of the values it was reading: (not drivers side airbag resistance)

Battery voltage: 12.0 V
1st level driver airbag resistance: 3.0 Ohm
2nd level driver airbag resistance: 3.0 Ohm
1st level passenger airbag resistance: 2.0 Ohm
2nd level passenger airbag resistance: 2.0 Ohm
Driver pretensioner resistance: 2.0 Ohm
Passenger pretensioner resistance: 2.0 Ohm
Driver side airbag resistance: 0.0 Ohm
Passenger side airbag resistance: 2.0 Ohm
Driver curtain airbag resistance: 2.0 Ohm
Passenger curtain airbag resistance: 2.0 Ohm
Driver knee guard resistance: 2.0 Ohm
Driver belt current: 24.0 mA
Passenger belt current: 24.0 mA
Front airbag exclusion switch current: 24.0 mA
Passenger pressure sensor current: 0.0 mA
Instrument Panel (NQS): Active
Trip computer: Active
Body computer: Active
Failure warning lamp status (from CAN): No error
Passenger airbag exclusion warning lamp (from CAN): No error
Seat belt warning lamp (from CAN): No error
Failure warning lamp: On
Passenger airbag&knee guard: Enabled
Passenger present sensor: Not present
Passenger airbag exclusion switch: On
Passenger airbag exclusion warning lamp: Off
Pretensioners cut-in: 0
Side airbag trigger: 0
Driver seat belt: Not fastened
Front passenger seat belt: Not fastened
Rear side airbags exclusion switch: On
Rear side airbag exclusion warning lamp: Off
Rear side airbags: Disabled by control unit
i decided to run the same test with the orange connector completely off, B100E was still there, as well as 2 other (probably not important since they were intentionally induced), but some reading were slightly altered with the orange connector completely off:

Battery voltage: 12.0 V
1st level driver airbag resistance: 3.0 Ohm
2nd level driver airbag resistance: 3.0 Ohm
1st level passenger airbag resistance: 2.0 Ohm
2nd level passenger airbag resistance: 2.0 Ohm
Driver pretensioner resistance: 7.0 Ohm < changed
Passenger pretensioner resistance: 2.0 Ohm
Driver side airbag resistance: 7.0 Ohm < changed from 0 to 7 Ohm
Passenger side airbag resistance: 2.0 Ohm
Driver curtain airbag resistance: 2.0 Ohm
Passenger curtain airbag resistance: 2.0 Ohm
Driver knee guard resistance: 2.0 Ohm
Driver belt current: 0.0 mA < changed. zero since there was no connection
Passenger belt current: 24.0 mA
Front airbag exclusion switch current: 24.0 mA
Passenger pressure sensor current: 0.0 mA
Instrument Panel (NQS): Active
Trip computer: Active
Body computer: Active
Failure warning lamp status (from CAN): No error
Passenger airbag exclusion warning lamp (from CAN): No error
Seat belt warning lamp (from CAN): No error
Failure warning lamp: On
Passenger airbag&knee guard: Enabled
Passenger present sensor: Not present
Passenger airbag exclusion switch: On
Passenger airbag exclusion warning lamp: Off
Pretensioners cut-in: 0
Side airbag trigger: 0
Driver seat belt: Fastened
Front passenger seat belt: Not fastened
Rear side airbags exclusion switch: On
Rear side airbag exclusion warning lamp: Off
Rear side airbags: Disabled by control unit
what areas can i look into the check connectors for the drivers side airbag? it could be unrelated to me dropping an item down the side. I have also been spending a bit of time in and around the OBD port so perhaps i have knocked something there?

next to the orange connector there is a black connector which doesn't have a plug (attached image), originally when i saw this i assumed it was for another module like heated seats or maybe electric seats, but now that i have seen the photo with yellow duct tape below, maybe the previous owner had something reconnected in a bit of a dodgy way. any idea what that black connector is for?

any ideas and direction will be greatly appreciated guys

sorry for the lengthy post, but hopefully the more info i can provide can help me diagnose this issue...
 

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There's a connection to the airbag through the steering column, sounds like this might be faulty and occasionally shorting out. Do be rather careful when working on airbags, mind.
 

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Discussion Starter · #3 ·
Should I remove the center circle in the wheel or below the steering column?

Any clues on what I should look for??

Thanks pete
 

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I've not done it myself. Have a look through the eLearn program for the 159, should be covered in there.
 

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I read the fault case being the seat airbag, drivers side, not the wheel airbag.

Follow airbag safe working rules and then use proper contact cleaner on the plugs and sockets.
 

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If you're getting a zero resistance, I'd be looking for a short circuit, melted, chafed or cut wire.
 

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Discussion Starter · #11 ·
re did the connector under the seat with compressed air and contract cleaner..

still no change.

there is some wiring next to the orange terminal which is wrapped up in yellow electrical tape, looks like this is done on all cars from factory according to the (few) pics i have seen...

might have to undo that electrical tape and check the wiring there.

i strongly believe it is in the seat area, as withe the connector on i get a low resistance, with the connector off i get a high resistance. although its not definitive.

I have no idea where any other connectors for the airbags are around the OBD port, or where the Control unit is, or in what direction the resistance is being measured.
 

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If the resistance value changed when you unplugged it, I would say the wiring is fine up to the plug, and the unit itself is fine. The return wire might be shorting out on the chassis mind.
 

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Discussion Starter · #13 ·
^ hoping the unit is ok

The first day it occurred it was quite intermittent. But after that it's stayed on constantly

Not sure where else to look at this stage.

Whereabouts is the unit located?
 

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Discussion Starter · #14 ·
This thing is really doing my head in

Nothing from under the seat came good..

Tried to trace the wires to under the carpet to near the fuse box. With no luck. Seems like all the wiring from the back of the car is travelling through the same path and new cabling is added to the rest so it is one big group of all the wires heading back..

Didn't really wanna remove the carpet and plastic panels to see it come fruitless..

=(
 
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