What's the "extra" connector in my steering wheel for? (2 Viewers)

[growe]

Hey all, I've done a bit of digging, but I can't for the life of me figure out what this connector coming out of the clock spring is wired for.

It's a black and green wire going into the same connector as the horn and cruise control.

The backstory is that I'm building a custom head unit and want to retrofit steering wheel volume controls. I've purchased a 2 wire style cruise control stalk and have got things working on the bench with an arduino. Next step is to install it in the truck, but I can't for the life of me figure out where the other end of these wires disappear off to. I can't find any mention of them in any wiring diagram and searching "random wire in steering wheel" hasn't been particularly fruitful.

Hoping some wizard sees this and happens to know.
Thanks!

 

[Trunk Monkey]

Year and model of truck would help.

 

[kerrye]

02 L here. I just replaced my clock spring. Had the same wires but it looked to me as if they simply dead ended. I couldn't figure any reason for them either. Could it be some kind of ground for the horn? I also couldn't figure out the horn was activated.

 

[kerrye]

An additional thought, I think there has to be some mechanism in the SRS computer for checking the ground on the airbag system since there's a code which sets of the light when this happens. I believe this disarms the airbag in some say since when my clock spring failed the horn and cruise would intermittently activate but the airbag didn't go off. If you look at the pictures of my clock spring I posted a few days ago, the wires were completely mangled with no insulation which suggests the airbag could easily have been energized the same way the horn and cruise were, but it wasn't. This is just educated speculation.

 

[growe]

Year and model of truck would help.

Oops, you're right! It's a '98 LX470.


I did manage to hunt down what it's for though! Basically, I backreferenced the connector that the cruise control wires run though, and was able to trace it down that way. Turns out it's a switch to activate the mic for the optional built-in cell phone (remember those? Wild times...)

If anyone is curious and wants to do something similar the easiest place I could find to tap into the wires was IH2, under the dash. It's a bit annoying because all of the wires a F****ng brown, but I just double checked the pinout with a multimeter and it was all good.

The final install:

 

[Mike NXP]

What are we looking at here, you swapped your cruise control lever?

 

[Dirt Ferguson]

It appears that the steering wheel was attached upside down or is this some phone-cam mirrored-image trickeration?

 

[Mike NXP]

It appears that the steering wheel was attached upside down or is this some phone-cam mirrored-image trickeration?

Hmm indeed, the mystery remains