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Discussion Starter · #1 ·
Hi All,

‘New’ ‘08 G8 Base owner here. Bought it a few days ago and I’m starting to go over everything.

Seller advised there’s always been issues with the front door speakers. Passenger never worked for him in 20k miles and drivers side has apparently gotten worse.

I have diagnosed no signal going to the passenger door or tweeter, and a ‘crippled’ or weak signal going to drivers door and tweeter. I know the fronts are essentially wired together. Center seems okay, as well as rears.
So I pulled the drivers door shell. Speaker looks new. Hooked in a good test speaker, same results as stock speaker. So it’s the signal. Then I pulled the drivers tweeter. Same results. And with tweeter disconnected, Same shoddy signal to the door.

Then I moved on to the radio. Here is where it gets interesting. When I pull the harness from the radio and re-insert, I get one second of beautiful perfect delightful sound from the passenger tweeter as well as door signal. Then it cuts out. I did not confirm drivers side since I left speakers unhooked. But this weird finding really has me stumped.

I’m not an expert on crossovers, could a bad capacitor cause this? The drivers side test results make me think it’s the radio unit failing. Tomorrow I can try a test speaker directly to the radio leads. But I’m thinking it’s a bad radio?

I’m posting to see if anyone has seen anything similar.

foxman
 

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Did you check if any of the speaker wires are shorted to ground? Short bursts of sound then a cutoff can be it going into protect mode when there isn't enough load. At least that's how my little shelf stereo amp acts when I put a sub on it with too little resistance and turn the volume up too far.
 

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Discussion Starter · #3 ·
I haven’t followed any of the wires fully. I think testing the radio directly with test speaker would identify wire issues
 

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If the stock speakers are fine, how does a test speaker id wire issues? It's the same wires, no?
 

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Discussion Starter · #5 ·
My next test I intend to hook a test speaker directly to the radio’s leads where the speaker wire harness clips into. I’ve found a wiring diagram so I figure using a good test wire(s) and clipping to correct pins at radio leads should by process of elimination tell me if it’s a wiring issue as you suspect.

Other than visual inspection, how else could I diagnose a ground fault? I don’t currently have a voltmeter but I’d be willing to pick one up.

let me know what you think and thanks for your input!
 

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Discussion Starter · #6 ·
I guess I could have simplified the reply. I plan to use a separate test wire to radio, not the stock wires.
 

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Visual could be easy, if you are lucky, or it could be really time consuming. I would much rather buy a multimeter or use a test speaker right at the radio than try to inspect the whole harness.

I don't really suspect that it's a wire issue as much as I was presenting it as an option. I've had both wiring and electronics issues before. Actually maybe having a little of both right now. Right rear door speaker cuts out completely under a certain volume. Same thing happened a while back with the other rear speaker due to a corroded connection. And my subwoofer power level is doing weird things, sometimes fine, sometimes poor quality, sometimes nothing at all. Wiring in the sub enclosure is fine. Ruled out the wiring between radio and amp. My current options are the radio itself isn't cleanly producing low frequencies, but somehow the rest is fine, or my amp or output connections from it are faulty.
 

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Discussion Starter · #8 ·
I’ll let you know my findings after the radio test this evening.
My subs sounds like the foams have failed or ripped, but still work. I have replacements ready to go in. I wouldn’t think that a subwoofer failure would cause front speaker issues.. Rear doors sound fine.
 

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Your problem sounds like my G8's stereo, previous owners doing hack jobs.
Someone put an aftermarket sub in the trunk didn't re-attach subs when he yanked it and left me stubs for re-wiring.
My hero....
 

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Discussion Starter · #10 ·
Well it took a few days but I had some more time to diagnose.

I didn’t want to pull the wires out of the plug to try a test speaker so I figured I would take a look at the subs instead since they sounded blown. Well it wasn’t the subs. Pulled everything up and they look fine. Unplugged them, same issues (front speaker failure). Unplugged the rear amp, same issues.

the subs sound blown, but I’ll tackle one thing at a time.

Center speaker and rear doors still work great.

I did some poking around and if I tapped into the center lead, I could get sound at low volume, but would cut out at any significant load. So maybe it is a short to ground?

I bought a working g8 radio off marketplace and eagerly tried that just to get the security Lock Screen. Guess the dealer has to unlock, good backup in case the radio has failed tho.

So next I guess I can try pulling the individual wires out of the plug so I can test the radio with the test speaker, and or checking the door boots for wire damage.

Could it be blown capacitors or something in the radio? Anyone ever have that? Now I’m thinking it’s wiring since all of the speakers look fine, and I haven’t seen any tampering from stock. No corrosion at any of the terminals either.
 

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The used head-unit will have to be programmed to the current vehicle's identification number before it will work correctly.
 

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Discussion Starter · #12 ·
Well I took a few hours and figured out how to remove the wires from the plug that goes into the radio. You have to gently unclip the smaller plug from the big one. I used a couple little flatheads. Then the blue retainer slides out sideways from the smaller clip. At this point I was able to verify the front door speakers and wires were fine by testing then in the rear speaker pins at radio.
So faulty radio.
Good thing I bought another.

I put everything back together for now, I can live with just rears for a bit. The rattling from the woofers was just the cardboard center cap that had popped loose, they sound fine now.

I’m guessing the replacement radio has to be plugged up to be security unlocked? Can any tech 2 tool do this, or is it dealer exclusive?
I’m considering doing the vim unlock and maybe some other tweaks I’ve seen to the replacement. Thinking about it, I should probably get it unlocked and verify it’s good before I get into that.

thanks for your help guys
 

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Reprogramming the radio is not dealer exclusive and is personally doable with both the proper tools and knowledge. There's at least one forum thread detailing the process. As far as I know, the head-unit has to be powered on in order to reprogram.
 
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