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why does onstar not work when I disconnect my disc changer?

2476 Views 17 Replies 6 Participants Last post by  ewill3rd
I had to disconnect my changer to use my iPod neo. The onstar doesn't work when the changer is disconnected. I reconnect the changer, onstar works fine. Seems crappy to me! Anyone know a way to fix?
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The OnStar audio is integrated into the car entertainment audio system. I'm not surprised that one affects the other.
well I realize that, but one would think the disc changer would not be an integral part of that relationship. At least I wouldn't. Don't they make adapters to "fool"onstar into thinking the system is all in its OEM state.
check blitzsafe or peripherial they should make what you need
Are you using the wiring from the changer to power up your... thingamajiggie?
Removing the changer should not affect OnStar operation, but depending on the model year they could be using the same E&C bus data line.
Whenever you request OnStar by pushing the button the VIU sends a control message to the radio requesting control of the speakers.
The CD changer also does the same. Since they are both on the same data bus they must be compatible with eachother. If you are using the ipod, and it's hooked to this bus to request control of the radio, the OnStar request may be lost due to device incompatibility with OnStar.

As I said though, this depends on what year your Escalade is.
FYI it is a 2002 escalade, with the tape dec/changer setup. FWIW, the ipod setup essentially fools the head unit into thinking the ipod is the disc changer. The ipod device interface plugs into the changer plug on the back of the head unit, entirely replacing the changer.
In that case my prior post is correct. From your description I gathered that was the problem.

The Ipod is taking over the E&C bus and the OnStar module can't take back control of the radio.
Just try to disconnect your Ipod and leave the CD changer out, I bet OnStar will work just fine.

That's how the IPOD "fools" the radio into thinking it's the changer, by taking control of the E&C bus.
If it was a newer model it wouldn't be an issue because the VCIM is now using the Class 2 bus to control the radio while the CD is the only thing on the E&C bus.
What you have is a device that is interfering with the designed operation of your OnStar system.
Just another update: I hit my onstar phone button, and while nothing was coming through the speakers, I told it to dial my cell phone number. Low and behold, it still worked. So the onstar is in fact functioning, just not able to get control of the speakers. I had a nice 5 second conversation with myself over my onstar. :D
You could wire in a switch to the E&C bus wire to disable your IPOD from controlling the radio when you want to use OnStar.
If you want to do something like that I might be able to find out which terminal it is in the CD changer connector.
ewill, since you seem to be an expert, do any of the individual wires on the plug that goes into the back of the head unit (not the disc changer harness) represent an individual speaker? My driver door speaker is out and I'm curious if I may have jarred something loose when installing my ipod adapter, I don't remember if I was having a speaker completely out before I installed (just got the vehicle from my rents after trading in my old lade).
The outputs from the CD changer plug are left and right only.
If you had one messed up it would take out all speakers on the left or right channel.
Does this problem occur on radio also or only from the ipod?

There are lots of wires from the radio and amplifier that go to the speakers but it depends on what options you have.
If I get some time, give me the last 8 digits of the VIN and I'll look over the schematics and tell you what might cause the LF door speaker to quit.

I have to go take some tests tonight and I am running late right now.
Problem occurs on radio, tape, ipod, and also when I restore the stereo setup back to normal. Is only the front driver door speaker.
For the uninitiated, just exactly what is On Star and will it work outside of the US?
Nyssa, OnStar is a cellular phone built into your car basically. It's tied into your cars communication system so it can send commands to other modules on the car to do things like remotely honk the horn or unlock the doors under remote control. It also has a GPS antenna so that someone can remotely identify your vehicle's location.
They can help you get where you are going, tell you where you are or track your vehicle if it's stolen. It's under the control of the OnStar center, if you have a problem you call an 800 number and as a subscriber they help you in time of need.
Visit for more info. As for whether or not it works outside the US... I don't know. I think other countries have variants of the service, or they may be tied into the same thing. I am sure the equipment or setup may vary based on the country you are in.

gort, get me the last 8 digits of your VIN. There are lots of variants in that system based on what options you have. It sounds like you probably just lost a door speaker but if you are handy with a voltmeter I can tell you how to check it. If you remove the door panel and disconnect the suspect speaker you can check for ac voltage at the connection. If it reads right you probably just need a speaker. With some wires and a AA battery you can check the speaker as well. Let me know.
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Thanks for that, suspected it might be something like that, but its good to know. Don't have an Escalade yet, but hoping to be able to get one sometime in the next 2-3 months so need to learn all I can first
The last 8 digits of my VIN are: 2R185866 . If I can just get detailed instructions on how to remove the driver door panel safely I'll be set! I know there are two screws on there I removed those once and tried pulling on the panel (as another member here mentioned was how it's done) but felt like it wasn't budging and I didn't want to try to force it.
For '02 to get the door panel off, pry the "mirror patch". There are some spring clips that hold it on.
Remove the small plate behind the door handle, then pull up on the inner edge of the window switch assembly. Disconnect the connectors and take out the 7mm head screw behind the switch assembly and the screw underneath the pull handle in the recess.
I pop out the reflector/lamp asm with a small screwdriver and disconnect the wires to it from the socket.
Then just lift straight up on the door pull to disengage the hooks on the inside of the panel.
Tip it out and disconnect any remaining connectors for the speakers or other switches on the panel.
Then you can access the speakers.

I don't have time right now to look at the schematics but you should be okay to figure out what's not working with the door panel off.
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