'17 X6 F16 - "Driver restraint system" error, "wire resistance too high"

[lauritzm]

I recently purchased a steering wheel extender for my 2017 X6 xDrive50i F16 https://www.949racing.com/product/xt...9-e46-e60-e61/ I was assured by the supplier that this would also fit an F16 X6. I have contacted them to get some feedback on this problem.

I had a local garage with knowledge of BMWs install the extender. The steering wheel extender comes with a wire harness extension that was installed. It seemingly worked fine, all buttons etc. on steering wheel working no errors, then a few weeks later (very few miles driven in those weeks) I got an error of "Driver restraint system". I had it diagnosed at the BMW dealership and they said I should do a full airbag replacement, 2000 dollars. The error itself is "wire resistance too high" for driver side airbag (when viewed at a local garage with Carly/similar 3rd party device, I do not know if the BMW dealership have tools to see more detailed or other errors). The BMW dealership did not open up the car, but based it on their diagnostics device.

The car has the original battery, so it is 6 years+ by now. 84k miles mostly in Texas.

I do not have much mechanical knowledge, so I am pondering what my approach should be. I would love some help and input.

1) Have dealership change battery and reset error? Battery is probably towards the end of its lifespan anyways, although it passed BMW service inspection just fine so I am not sure if that is causing the problem.
2) Revert the extender, although I really like it, removing the wire harness extensions and then reset the error.
3) Have the BMW dealership or another garage with BMW tools needed to reset the airbag system errors do that, maybe it was a one-time error that goes away (seems doubtful).

Other thoughts?

[RED_Y_]

Kind makes sense, longer the cable will have higher resistance and airbag system is very sensitive for such things. Best way to test the theory is to remove the harness and clear the error.

[lauritzm]

Originally Posted by RED_Y_

Kind makes sense, longer the cable will have higher resistance and airbag system is very sensitive for such things. Best way to test the theory is to remove the harness and clear the error.

Thanks. Yeah, I might have to just go that route.

I'm trying to figure out a way I can keep the extender which I love and still have an airbag (which I also love!), but maybe it was not meant to be. Will see what the supplier of the extension kit say as well.

[lauritzm]

I don't know if it helps, but I measured the voltage on the battery using Bimmerlink (ignition ON, engine OFF) and it shows 11.96V (which is definitely low, but not crazy low). I am not sure if this can actually cause the high resistance error though, from Ohms law if the current is the same then resistance should not increase when voltage drops, it should go down...

I think I have to revert.

[jbfrancis3]

The airbag circuitry is designed to be sensitive to small variances. The issue is no doubt caused by the extension harness.

I would try the following:
- Remove the aftermarket wiring harness extension
- Remove the spacer
- Reconnect the "final" factory harness to the factory connector (as it would be connected prior to adding the aftermarket extension)
- Leave the green/black 90 degrees connectors off the airbag
- Put back the spacer
- Position airbag part of the way in the recess and attempt to reconnect green/black 90 deg connectors
- Theory is you can get away with no using the wire extension harness

[lauritzm]

Originally Posted by jbfrancis3

The airbag circuitry is designed to be sensitive to small variances. The issue is no doubt caused by the extension harness.

I would try the following:
- Remove the aftermarket wiring harness extension
- Remove the spacer
- Reconnect the "final" factory harness to the factory connector (as it would be connected prior to adding the aftermarket extension)
- Leave the green/black 90 degrees connectors off the airbag
- Put back the spacer
- Position airbag part of the way in the recess and attempt to reconnect green/black 90 deg connectors
- Theory is you can get away with no using the wire extension harness

Interesting. Might open it up and give this a go! Thank you for the suggestion. Might be a stupid question, but do you know if there is a lengthening/shortening of the wires to note when turning the steering wheel that could cause issues if I were to go this way?

If that does not work, I can always revert to stock.

[jbfrancis3]

Originally Posted by lauritzm

Interesting. Might open it up and give this a go! Thank you for the suggestion. Might be a stupid question, but do you know if there is a lengthening/shortening of the wires to note when turning the steering wheel that could cause issues if I were to go this way?

If that does not work, I can always revert to stock.

No, there is a component - often called a clockspring - in between steering column and steering wheel that allows for circuitry to be maintained with multiple rotations of the wheel. And so the input and output connectors are in a fixed position, meaning you don't risk stretching an already taught wire.

[lauritzm]

Originally Posted by jbfrancis3

No, there is a component - often called a clockspring - in between steering column and steering wheel that allows for circuitry to be maintained with multiple rotations of the wheel. And so the input and output connectors are in a fixed position, meaning you don't risk stretching an already taught wire.

So that is what the clockspring is for, that makes sense. Thank you again!