Which wires in steering column are from radio volume controls

[wachuku]

Does anyone know which wires coming from the steering column are the ones coming from the steering wheel volume controls?

Or, does anyone know which wire(s) on the radio harness interface with the steering wheel volume controls?

'97 STS, regular, not bose, radio.

[CadillacSTS2003]

why
they are interfaced through the data class 2 system
its not a simple plug and play fix to use them with another radio
you need a special adapter and whichever one you buy will include instructions on how to do it...

[wachuku]

In light of rhe response above I think I should focus my question on the first part:

Does anyone know which wires coming from the steering column are the ones coming from the steering wheel volume controls?

I want to interface the steering wheel volume control with some custom audio gear I'm making that involves an ADAU1701. (http://www.analog.com/en/audiovideo-...s/product.html)

Without getting into details, I would like to know if anyone knows which wires from the steering column connect to the volume controls, assuming those wires are not integrated into the data class 2 inside the steering column.

[Cliff8928]

Originally Posted by wachuku

Without getting into details, I would like to know if anyone knows which wires from the steering column connect to the volume controls, assuming those wires are not integrated into the data class 2 inside the steering column.

Maybe CadillacSTS2003 could correct me if I'm wrong, but I believe the steering wheel control wire goes to the IPC (gauge cluster). There is not a dedicated wire for volume up, volume down, Temp, Fan, etc.. but a single wire for all the controls. When you press the buttons it varies resistance on that wire and that's how it knows what to do. ex. Vol down @ 294Ω, Vol up @ 1270Ω etc...

The IPC is what translates the varying resistance into a Class 2 signal.

I don't have any info for a '97, but on a '98 Eldo, it's a Blue wire at connector C2 pin B11 on the IPC.

[wachuku]

Wow cliff8928 that's great info. That seems like a pretty tough interface to hack into.

Those resistor values you stated -- for your car at least -- are they exact, or are they just arbitrary numbers you're using as examples?

[wachuku]

And thank you Cliff8928 for the info you've already provided. I'm not sure I ever would have been able to figure out such an interface on my own.

[CadillacSTS2003]

cliff hit it dead on

the resistance sent by the switch is sent though the data class and interpreted by the data bus and performs the operation...
the only difference is on the bose system in the <98 Seville and All 92+ Eldos the volume is controlled by the amp control box

[Cliff8928]

Originally Posted by wachuku

Wow cliff8928 that's great info. That seems like a pretty tough interface to hack into.

Those resistor values you stated -- for your car at least -- are they exact, or are they just arbitrary numbers you're using as examples?

Those values I mentioned should be at least for the Eldorado and pre-98 Seville but may be entirely GM-wide.

The resistance values are...

Temp Down - 6980Ω

Temp Up - 2370Ω

Fan Down - 1180Ω

Fan Up - 715Ω

Select Down - 475Ω

Select Up - 348Ω

Vol Down - 294Ω

Vol Up - 1270Ω

http://www.pac-audio.com/ has interfaces for the steering wheel controls also...