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Discussion Starter · #1 ·
i own a 2002 envoy slt with a bose sound system, i recently installed a alpine cda 9887 HU and hooked everything up right with a pac audio unit that bypass's my onstar(cause i dont use it anyways) but i cant get any sound from the speakers the deck works and powers up fine the pac unit chime works fine i just cant get any sound does anyone know what i am doing wrong? or do i have to take out the bose systme and replace it all?
 

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You know the Bose system has a remote amp in the rear right side panel, and the speakers are hooked up there, not at the old head unit?
 

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Discussion Starter · #3 ·
yeah my amp is located underneath the back seat on the passenger side and the unit that i used to bypass my onstar (C2R-GM24) is supposed to be a plug and play adapter so all u gotta do is plug the right speaker jacks into the rear of the deck and it is all supposed to magically work...but it doesnt.
 

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You know the Bose system has a remote amp in the rear right side panel, and the speakers are hooked up there, not at the old head unit?
Yes but the speaker outputs are still at the HU.


But to the OP, are you just using the factory Bose speakers? If so you'll need to buy a Bose interface module IIRC. Or bypass the factory amp, I cant remember which.:suicide:
 

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:eek: :eek: :sadcry: I'm so embarrassed. I answered without pulling out the schematic to confirm. I'll stay in the Offroad forum, I promise. :hopeless
Its ok man, the Bose HUs send a class 2 signal along with a set of flat response signals (for all speakers) to the Bose amp which then acts as a regular amp using the class 2 signal for volume/eq. Now Im pretty sure this is how it works but Id like someone to verify this.
 

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Discussion Starter · #8 ·
the bypass i used is the pac audio c2r-gm24 unit:

For most 2003-2006 GM SUV's and trucks using Class 2 serial data. Retains all safety and warning systems. For use when OnStar is not present or retained.
• Retains all warning chimes including back-up chimes, memory seats, low fuel, door/hatch ajar and others.
• Provides a +12volt accessory wire.
• Retains R.A.P. (Retained Accessory Power).
• Supplied wire harness to connect aftermarket stereo to factory speakers.
• Connects to vehicle with standard Bose® audio systems.
Compatible Vehicles (with or without Bose®):
2000-2005 Cavalier, Sunfire, Impala, Monte Carlo
2002-2003 Malibu
2002-2005 Grand Am
2002-2007 Trail Blazer/Envoy (SLE), Montana, Venture, Rainier, Terraza, Uplander
2003-2004 S-10
2003-2006 Tahoe, Suburban, Yukon, Sierra, Silverado, Avalanche, Bravada
2004-2007 Grand Prix
2005-2008 Corvette, Canyon, Colorado, H3
**If Premium Bose® is bypassed:
2002-2004 GMC Envoy (SLT), Chevy Trailblazer (SLT)
2003 Hummer H2
2003-2006 Cadillac Escalade, GMC Denali (Sierra/Yukon), SSR
 

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Its ok man, the Bose HUs send a class 2 signal along with a set of flat response signals (for all speakers) to the Bose amp which then acts as a regular amp using the class 2 signal for volume/eq. Now Im pretty sure this is how it works but Id like someone to verify this.
The schematics I have for 2004 show the Bose head unit sends low level signals to the amp using the SAME pinout that the non-Bose head units use for speakers. So there needs to be a bypass jumper harness installed at the Bose amp location to get the new head unit outputs to the speakers. Because the speakers only get connected at the Bose remote amp. At least in 2004.

What I learned was that the Bose rear amp in LWB vehicles is in the left rear, instead of the SWB right rear.
 

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i'm glad I never had bose
 

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Discussion Starter · #11 ·
well i got it figured out, had to order a new harness it is the 0S-2 harness from pac audio:

OnStar® Interface for GM Class 2 non-Bose vehicles. The OS-2 uses a Data Link Controller chip (DLC) that is specifically designed for connecting to GM's Class 2 data bus.
• Safe & Sound Class 2 circuitry will not disable vehicle data bus even if interface loses power.
• OnStar® active LED and Ignition on LED for visual indication.
• Provides +12v switched accessory output. No more searching for switched +12v in fuse box or kick panel.
• Smart Sense Mute output to either mute the aftermarket radio or to turn it off when OnStar® is active.
• Retains door chimes when used with optional CM1 chime module.
• New radio will operate with the vehicle RAP (Retained Accessory Power) system.
Compatible Vehicles:
2000-2005 Impala, Monte Carlo
2002-2007 Trail Blazer/Envoy (SLE), Montana, Venture, Rainier, Terraza, Uplander
2003-2006 Tahoe, Suburban, Yukon, Sierra, Silverado, Avalanche, Bravada
2004-2007 Grand Prix
2005-2008 Corvette, H3, Colorado, Canyon
2007 Silverado/Sierra (Classic ONLY)
**If Premium Bose® is bypassed:
2002-2004 GMC Envoy (SLT), Chevy Trailblazer (SLT)
2003 Hummer H2
2003-2006 Cadillac Escalade, GMC Denali (Sierra/Yukon), SSR
2005-2006 Equinox and 2006 Torrent are not supported at this time



stupid onstar.....
 

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Discussion Starter · #13 ·
acually the second one is the one to get, the first bypass only works if u dont got onstar so i guess ya if u are onstarless but still got bose then that first one i listed is the one but i needed one that would bypass my onstar but still have it plugged in..lol it is confusing but i am glad i finally got it worked out and now i can acually listen to my new stereo!:thumbsup:
 

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Discussion Starter · #15 ·
love the 9887, even with just the stock bose speakers right now it was a million times improvement and it is pretty easy to learn. i havent bought the ipod cable for it yet but i plan on getting it.:hail:
 

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acually the second one is the one to get, the first bypass only works if u dont got onstar so i guess ya if u are onstarless but still got bose then that first one i listed is the one but i needed one that would bypass my onstar but still have it plugged in..lol it is confusing but i am glad i finally got it worked out and now i can acually listen to my new stereo!:thumbsup:
hey i have a 2002 envoy sle with onstar i can't find the 0S-2 module do you have the full name of it and is there anyway to completly bypass or shut off the onstar i dont want it in my car thanks:)
 
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