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Discussion Starter #1
Don't ask me how :( I grounded a 18 gauge wire onto the chassis of the head unit when it was connected to the factory harness. The lights in the car dimmed thats how much current went through it (car was on with alt running). It now makes all sorts of noise, as if the internal ground is badly damaged. It does still start up and play music, so I am lucky it isn't totally fried.

Any ideas? :worried:
 

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Might be a lost cause. But what hu?
 

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are you sure you didn't ground the head to the dash light wire? rather common, and will force the light circuit to ground to the antennae shield. make sure you have the right ground selected from the car, and turn the head lights on while probing, and make sure you do not tap into a databuss connector. what car is it? and, yes, especially if it still turns on, a ground circuit can be repaired, it's just the extent of any damage that makes the question not "if", but "how much"
 

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Discussion Starter #5
are you sure you didn't ground the head to the dash light wire? rather common, and will force the light circuit to ground to the antennae shield. make sure you have the right ground selected from the car, and turn the head lights on while probing, and make sure you do not tap into a databuss connector. what car is it? and, yes, especially if it still turns on, a ground circuit can be repaired, it's just the extent of any damage that makes the question not "if", but "how much"
It was an 18ga unfused wire from the battery. The amount of current that went through it dimmed the lights.

The car is a 97 Saturn SC2
 

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It was an 18ga unfused wire from the battery. The amount of current that went through it dimmed the lights.

The car is a 97 Saturn SC2
HOW did you ground it to the HU chassis? did you simply touch it and BAM..?

Did you screw it into something, run the wire through a hole?

Obviously, that shouldn't have happened...

If you happened to bridge across ground and something else, that would make sense..
 

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Discussion Starter #8
HOW did you ground it to the HU chassis? did you simply touch it and BAM..?

Did you screw it into something, run the wire through a hole?

Obviously, that shouldn't have happened...

If you happened to bridge across ground and something else, that would make sense..
Yeah the first one. I was having a bit of noise, which I eliminated by removing the HU and fiddling with wires. I removed the wrong wire which I thought was fused, and it actually wasn't. It swung around and hit the case and boom, melted some of the metal on the cage, dimmed the lights and then there was alot of noise (more than before) coming from the HU.

I am going to try grounding the RCA's seperate tonight to the common HU ground which I think may fix the issue - this way it doesn't have to ground through the internal ground.
 

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grounds aren't fused...

They also don't melt metal on the cage when they "brush" against it... You picked the wrong wire..

You fried your HU with something other than ground.. and it's likely you aren't going to fix it...
 

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Discussion Starter #10
grounds aren't fused...

They also don't melt metal on the cage when they "brush" against it... You picked the wrong wire..

You fried your HU with something other than ground.. and it's likely you aren't going to fix it...
No, like I said the ground didn't touch. A live 12v wire did. The internal ground for the amplifier is damaged, thus not grounding the RCA shields properly.

By grounding the RCA outer shell seperately you eliminate the requirement to use the internal ground, which I think is the problem. When the car is off, the noise isn't as bad, making me think it is a ground issue. We'll see what happens.
 

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No, like I said the ground didn't touch. A live 12v wire did. The internal ground for the amplifier is damaged, thus not grounding the RCA shields properly.

By grounding the RCA outer shell seperately you eliminate the requirement to use the internal ground, which I think is the problem. When the car is off, the noise isn't as bad, making me think it is a ground issue. We'll see what happens.
You never said a live wire touched... that was my deduction... see... can't do the work, without the proper info...

If the internal ground for the amp is damaged, NOTHING you will do, will fix it, not outwardly.. I used to repair HU's..

If you skirt by on this one, I'll be surprised.. NOT that I don't want all to be well, quite the contrary.. I just know this may not end well...

Good luck, let us know how it goes..
 

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Discussion Starter #12
You never said a live wire touched... that was my deduction... see... can't do the work, without the proper info...

If the internal ground for the amp is damaged, NOTHING you will do, will fix it, not outwardly.. I used to repair HU's..

If you skirt by on this one, I'll be surprised.. NOT that I don't want all to be well, quite the contrary.. I just know this may not end well...

Good luck, let us know how it goes..
Thanks for posting. Is there some sort of jumper/fuse I can resolder on the board then? I don't mind opening it up.
 

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Thanks for posting. Is there some sort of jumper/fuse I can resolder on the board then? I don't mind opening it up.
There are far too many "depends" to say... if your troubleshooting doesn't work, you might consider repair @Lifetime Service or United Radio..
 

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Discussion Starter #14
Want to update. I wound bare wire around the RCA's and then attached to the HU chassis, and poof - all the noise is gone completely - like a brand new unit.

Here is proof there is a fix for blown RCA shield grounds! :)

If anyone is having any noise issues this is a great way to attempt to eliminate it.

Thanks for the advice Aaron I got lucky.
 

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Want to update. I wound bare wire around the RCA's and then attached to the HU chassis, and poof - all the noise is gone completely - like a brand new unit.

Here is proof there is a fix for blown RCA shield grounds! :)

If anyone is having any noise issues this is a great way to attempt to eliminate it.

Thanks for the advice Aaron I got lucky.
Common "fix" for the fryanear pico fuse debacle...

Chances are you melted/evaporated a trace on the PCB or sometimes they put a 0 ohm "resistor" in there for protection of said instances.

This means though, that your ground thru your RCA was better than the ground to the headunit, may wanna look into that.
 

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Want to update. I wound bare wire around the RCA's and then attached to the HU chassis, and poof - all the noise is gone completely - like a brand new unit.

Here is proof there is a fix for blown RCA shield grounds! :)

If anyone is having any noise issues this is a great way to attempt to eliminate it.

Thanks for the advice Aaron I got lucky.
Glad to hear it!!

I was worried... but you just shown how the Pico fuse can be a real *****..
 

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Common "fix" for the fryanear pico fuse debacle...

Chances are you melted/evaporated a trace on the PCB or sometimes they put a 0 ohm "resistor" in there for protection of said instances.

This means though, that your ground thru your RCA was better than the ground to the headunit, may wanna look into that.
By description, I thought it was far worse.. :laugh:
 
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