Bad luck or bad wiring?
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Bad luck or bad wiring?
So I had a bad PAC GMOS-2Bose go bad one day after the initial. Not enough volts going to B3 wire on radio connector inside the car.
I replaced the PAC GMOS-2Bose with an identical one from Cartoys, where I bought the first one, only different cartoys location. Things were good for 2 days. Today the audio quit again, same situation as before!
I haven't pulled the thing out yet but I'm guessing its the same problem.
So I went to Frys and asked them for an adapter to fit thinking maybe I have purchased from a bad batch. They gave me an AXXESS GMOS-04.
Cartoys also initially gave me the GMOS-04 also but I told them I needed the OS2 so thats what I got.
My question is does anyone have ideas on what is happening, why these things are going bad?
Should I have started with the GMOS-04?
I'm going to install the 04 and see what happens unless that is a no-no.
Any input is appreciated!
I replaced the PAC GMOS-2Bose with an identical one from Cartoys, where I bought the first one, only different cartoys location. Things were good for 2 days. Today the audio quit again, same situation as before!
I haven't pulled the thing out yet but I'm guessing its the same problem.
So I went to Frys and asked them for an adapter to fit thinking maybe I have purchased from a bad batch. They gave me an AXXESS GMOS-04.
Cartoys also initially gave me the GMOS-04 also but I told them I needed the OS2 so thats what I got.
My question is does anyone have ideas on what is happening, why these things are going bad?
Should I have started with the GMOS-04?
I'm going to install the 04 and see what happens unless that is a no-no.
Any input is appreciated!
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after some searching, I found some folks with the GMOS-04 are bypassing the adapter for the amp wire as its not putting out enough volts.
That is my problem with the GMOS-02. So I might bypass it as well. Some folks use a relay for it connecting the blue/white wire of the radio to it. What will that buy me over not using a relay for the amp power lead?
thanks!
That is my problem with the GMOS-02. So I might bypass it as well. Some folks use a relay for it connecting the blue/white wire of the radio to it. What will that buy me over not using a relay for the amp power lead?
thanks!
Last edited by C5 Hardtop; Aug 8, 2009 at 08:07 PM.
Safety Car
Joined: Sep 2006
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From: Greer, SC
I remember hearing/reading that one of the integration modules being sold for our cars was not very good build quality wise. My buddy (The Komoman) advised me not to get that module. That is why I went with the Peripheral GMAH24. Not sure if it is the same module you have but check out the FAQ's at the top. I believe the information on the integration modules is there. If it is the one you have then I can't say I'm suprised.
Safety Car
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From: Greer, SC
Thread Starter
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well, nobody around here listed on the Peripheral website is open today that has one in stock.
What is the relay for, I'm wondering why I need that.
Can I just bypass the PAC adapter with the amp P.CONTROL blue/white wire from the HU? That way wire B3 will have enough power.
What is the relay for, I'm wondering why I need that.
Can I just bypass the PAC adapter with the amp P.CONTROL blue/white wire from the HU? That way wire B3 will have enough power.
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Tech Contributor
Joined: May 2003
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From: North Augusta, SC
Check out this thread for some scary info about the GMOS 
Read it all, but scroll down to post 41 for the GOOD news. It was made to work, but it took a bit of creative wiring. Adding the relay might work, but then the question is which relay should you buy, one with a 5v coil or a 12v coil.
If the 02 is anything like the 04 I might be tempted to just buy a GMAH24B & GMAHCM (you need both).
Read it all, but scroll down to post 41 for the GOOD news. It was made to work, but it took a bit of creative wiring. Adding the relay might work, but then the question is which relay should you buy, one with a 5v coil or a 12v coil.
If the 02 is anything like the 04 I might be tempted to just buy a GMAH24B & GMAHCM (you need both).
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I read that thread, what a POS GMOS-04! Shakey speedo?
Glad I come here and get educated by my great professors!
I think I'm going to take one of your tips Mark and bypass the adapter and go to the wire for the the amp (wire B3) until I can find a Peripheral in stock (Sonic is backordered for the bose one). I just don't get what the relay would buy.
The GF and I want to go for a drive today. She is really excited about having the DVD player so I need to get the audio working!
Glad I come here and get educated by my great professors!
I think I'm going to take one of your tips Mark and bypass the adapter and go to the wire for the the amp (wire B3) until I can find a Peripheral in stock (Sonic is backordered for the bose one). I just don't get what the relay would buy.
The GF and I want to go for a drive today. She is really excited about having the DVD player so I need to get the audio working!
Tech Contributor
Joined: May 2003
Posts: 7,035
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From: North Augusta, SC
The GMOS is putting out a low amperage 5v. If you used that 5v signal to pull in a relay, then had the relay contacts put 12v onto B3, it would simulate the GMOS putting out 12v.
My only question is what voltage the GMOS is putting out. If it's trying to put out 12v, but the load is pulling it down to 4.5v, then you may burn out the coil if you use a 5v relay.
My only question is what voltage the GMOS is putting out. If it's trying to put out 12v, but the load is pulling it down to 4.5v, then you may burn out the coil if you use a 5v relay.
Safety Car
Joined: Sep 2006
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From: Greer, SC
Honestly, I'd scrap the GMOS and just buy the quaility piece even though it means waiting to have a functional head unit for a few more days. You have already spent a lot of time with this and my guess is will spend a lot more until you just replace the POS module.
As my grandpa once told me many years ago....You can't polish a turd!
As my grandpa once told me many years ago....You can't polish a turd!
Thread Starter
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Ha-ha, I do feel like I'm polishing a turd, or putting lipstick on a pig! 
The GMOS-04 is going back. Never took it out of the package!
I soldered the blue/white wire from the radio (P.CONT) to the blue wire of the GMAH24B output harness which leads to the amp wire (B3) of the radio harness. Then also cut the GMAH24B output wire so I'm not using the amp output of the GMAH24B. So in short now I'm using the P.CONT voltage to supply current to the B3 wire.
Next, I powered the HU and it works!! Yipee! Hopefully this wont start my car on fire! j/k. I think it will be fine until I get the Peripheral GMAH24B product in my hands.
Thanks a bunch!!!
The GMOS-04 is going back. Never took it out of the package!
I soldered the blue/white wire from the radio (P.CONT) to the blue wire of the GMAH24B output harness which leads to the amp wire (B3) of the radio harness. Then also cut the GMAH24B output wire so I'm not using the amp output of the GMAH24B. So in short now I'm using the P.CONT voltage to supply current to the B3 wire.
Next, I powered the HU and it works!! Yipee! Hopefully this wont start my car on fire! j/k. I think it will be fine until I get the Peripheral GMAH24B product in my hands.
Thanks a bunch!!!
Last edited by C5 Hardtop; Aug 9, 2009 at 04:35 PM. Reason: clerification
Thread Starter
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no, couldn't find one. I just supplied the amp wire with the appropriate voltage as a hack (bypassing the PAC adapter), and viola!
This will just buy me time till the Peripheral component arrives!
This will just buy me time till the Peripheral component arrives!
