2005 New Beetle: change steering wheel to Audi TT?

[Shenandoah]

Folks,

This is probably a long shot, but I'll ask anyway:

The steering wheel on my 2005 New Beetle is kind of getting "gummy" (it's the perforated plastic/rubber version) and I would like to replace it with a leather Audi TT steering wheel.

The Beetle steering wheel air bag has two 2-pin connectors labeled "1" and "2". Connector 1 is green and Connector 2 is orange. Each connector has a ridge on the male connector. The ridge on the green connector is on the left side. The ridge on the orange connector is on the right side.

The Audi TT airbag has a single 2-pin connector that is purple. This connector is the same style as the Beetle connectors, but the ridge is in the center.

I installed the Audi TT steering wheel and cut the ridge off the orange connector and plugged it in to the Audi TT airbag. The green connector is not plugged in to anything. Started the car up and the airbag light is on. Scanned with VCDS and am getting a code for the #1 connector (that is the one that is not connected to anything).

My question is: Can I splice the two connectors together into one connector so the module thinks both connectors are connected? I know this is a long shot for an answer, but maybe some has done something similar?

I've noticed on the Golf and Jetta there is only one connector for the airbag. For some reason, the New Beetlee has two?

Thanks!

Eric

Anyone elxe

 

[RexNICO]

Sounds like your Beetle has a 2 stage bag. While I’ve seen write ups of people putting a 2 stage bag in a 1 stage case, it sounds like you’re trying to do the opposite. Which I’ve never heard/seen.

My suggestion would be to find an MKV wheel w/ 2 stage bag or the same from an Audi TT MK2.

 

[Shenandoah]

RexNICO,

Yes, after doing some more research and looking at the wiring diagrams in my Bentley, the Beetle has dual igniters for the steering wheel airbag. Earlier year Beetles had a single igniter. The Audi TT steering wheel/airbag has a single igniter.

I'm going to try a 2.2 ohm resistor in the 2nd igniter and see if that fixes the airbag light and code.

Thanks.

Eric

 

[wonneber]

I don't know if measuring the resistance of a igniter will set it off but 2.2 ohms seems low to me.
If your brave and measure it please let us know what happens.

 

[Shenandoah]

wonneber,

No, not going to try to check the resistance across the igniter. I found the 2.2 ohm value for the steering wheel airbag on a write up from VW Vortex where folks were installing a steering wheel without an airbag. I've ordered some resistors and will post the results.

An interesting find: As I mentioned, my Beetle has two igniters for the steering wheel airbag. One connector is orange, the other green. The connector for the Audi TT airbag is purple. Each male plug (wiring side of car) is similar with the exception of the location of a "ridge" on the plug. The ridge matches the small, female plastic part that goes over the two pins of the igniter on the airbag. The small, plastic female part can be removed from one airbag and used on another airbag. I could take the Green female plastic part and put it on the Audi TT that has the purple female part. That way I wouldn't have to modify or swap connectors.

Eric

 

[Shenandoah]

Folks,

Just to follow up. I stopped by the local Radio Shack today to see if they had any 2 ohm resistors. They did not, but they did have a 5-pack of 1 ohm resistors, so I purchased those. I took two of the 1 ohm resistors, twisted the ends together and soldered them. I then soldered these two 1 ohm resistors (in series) to the 2nd airbag igniter. Put everything back together, cleared the airbag fault codes and all is good. The airbag light comes on briefly, like normal, then goes out. No codes show up when scanning with VCDS.

Eric

 

[RexNICO]

Not to state the obvious, but there's a chance if/when this airbag ever needs to deploy, that it will do so with slightly less force (probably not the best word).

I'm not trying to sway you 1 way or the other, just making sure anyone that might come across this thread in the futures thinks about the differences in how a single stage trigger vs a dual stage functions on a single stage bag. Obviously better than no bag at all.

 

[Shenandoah]

RexNICO,

The original Beetle airbag had two igniters, two completely separate circuits. The Audi TT has a single igniter (like the Golf and Jetta). I installed the Audi TT steering wheel and airbag (with a single igniter). The way it is installed in my Beetle is how it would be installed in the Audi TT.

A dual-stage airbag has two inflator modules connected to one airbag. Each inflator module has a different power rating; say for example, a 70% charge in one inflator and a 30% charge in the other. The igniter triggers the inflator in the airbag. The inflator module is matched to the airbag. The voltage or current to the igniter does not determiner how "strong" the airbag goes off.

It would be a different story if I was using the Beetle airbag with only one igniter (instead of two).

Eric

 

[RexNICO]

Thanks for the correction. My understanding was different.

I think it still leaves the possibility for someone to use the incorrect stage trigger and not have the airbag deploy in lesser accidents, which some may want??

I've also seen example of people wiring both triggers to the same connection (dual stage car, single stage bag) or 1 trigger to both connections (single stage car, dual stage bag).