Sirius Radio connection

TonyMazz · July 7, 2005

I have an 04' Tahoe and had a sirius sportster installed. It fires up when ign is on and shuts off when ign off.

I am looking for a supply wire to keep the sirius powered up similarly as the radio for the 5-10 minutes after the ign goes off...and all shuts off once the door is opened.

Installed tells me that it's a low voltage signal that does this and I can't do it. I am not an electrician but suggest that the radio requires 12 v. and other things that work require 12v....

I read somewhere that there is a 12v supply wire for the sun roof that is available in the harness even if you have no sunroof (I don't)

Any suggestions what I can tell the install tech ??

Thanks

GM-Tech · July 7, 2005

Without knowing what low voltage signal he's talking about, and how this is causing the sirius to shut down, there's no way to know what to tell him.

Is the sirius monitoring class 2 data? That's the only low (toggling from 0 to 7 vdc actually) voltage I can think of that would be on the radio harness. But I don't see how the sirius being tied into that would cause it to go off the moment the key is turned off. Several things on the class 2 buss are awake for a while after the key is off.

If the sirius operates off the same power circuit as the radio, it should have power available to it just as long as the radio does.

Need MUCH more info.

hutchyx · July 8, 2005

I might be wrong here... but i believe the sirius unit is a stand alone unit not having having anything to do with the class 2 data.

The installer just wired it to a ignition switched source rather than a Retained Accessory Power source. Shouldn't you be able to find a RAP source behind the radio and tap into that?

TonyMazz · July 9, 2005

Sorry for any confusion....

Specifically, I have an aftermarket Sirius radio that currently is powered from the ignition....hence when the key is turned to off the sirius radio shuts down abruptly.

During which the dash, radio etc remain powered until such time as I open a door.

My desired condition is that I (with your help) identify a wire that remains powered with a 10-12v dc that I can hook up my sirius to and have it follow suit to shut down when a door is opened.

I am hoping that you'd help me identify a wire that can be tapped to do this function.

The guys that installed my sirius radio informed me that it is not possible, and I suggest that since there are systems that need 12v there must be a line some where that can be tapped into...I just don't know where / what it is with out a service manual etc.

Can you help ?

Thank you for your help

GM-Tech · July 9, 2005

Okay, here's how it works. The windows and radio are turned off by the RAP function by a class 2 message from the body control module, so this doesn't help you. The only other item that is controlled by RAP and done so externally, is a sunroof.

If you don't have a sunroof, I doubt the wiring is there. If you go to the BCM and connector C2 (gray connector, 24 pins), terminal B3, a dark blue wire, is the control circuit for RAP for the sunroof. See if that wire exists. I'm sure the pin exists in the BCM, but whether or not there's actually a wire in that cavity is another question. This circuit energizes or de-energizes the sunroof relay by sending 12v to the control windings. I would say it should be able to power a Sirius radio.

GM-Tech · July 9, 2005

BTW, the sunroof relay would be on the right side, against the A pillar, a foot or so off the floor. It would have four wires, Dk. Blue, Orange, Black and Black. The dark blue is the one that comes from the BCM. Even if you don't have the relay, you can see if the connector is there for it, though I think that's not likely.