Strange power wire problem

[focushead]

I am having a very strange problem with the power wire running from my battery. It has been installed in the car for a few weeks although I haven't had an amp in there lately. I went to test it today and had this problem:

I tested the wire for voltage between it and the ground and it reads around 12 volts. However, I tried to rub it against the ground (Bad idea I know) but there are no sparks!!

So my assumption is that there is not a lot of current able to pass???

I can't make sense of it, if there is a voltage then clearly everything is connected. There is no resistance across the fuse on the wire.

If anyone can help please let me know.

I should add that this has of course worked just fine in the past, usually there's so much juice pumping that it will practically solder itself together if the power and ground touch.

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[gckless 5,000+ posts]

Why are you touching them together????

Did it read 12V after you touched them also? What's it read exaclty, both engine on and off.

 

[focushead]

I'm touching them together because i'm crazy....

It read 12V after I touched them.

I am at work so cannot test further but it read about 12.5V off, did not test while on.

Why is there little to no current passing through?

 

[gckless 5,000+ posts]

I'm touching them together because i'm crazy....It read 12V after I touched them.

I am at work so cannot test further but it read about 12.5V off, did not test while on.

Why is there little to no current passing through?

If you're dumb enough to be purposely touching those wires, chances are you jacked something else up too. Good luck.

 

[focushead]

Thanks for the help, obviously no one has accidentally touched the wires together before.

 

[focushead]

Sorry for the animosity, I'm just at a real loss here. I know it's obviously a bad idea to touch the wire to the ground, but honestly, it's a wire straight from the battery with only a fuse in between. It reads a voltage so the fuse must not be blown (although perhaps somehow defective.)

How is this possible?

 

[richericks 10+ year member]

Other than you touching the positive to ground, I'm not sure I understand the problem. Are you saying that when you touch the power cable for the amp to the ground cable for the amp, nothing happens (sparks and fire and whatnot), but you are getting 12v-12.5v on your DMM when you measure the voltage without the car running? Seems normal to me (aside from the whole touching the two cables together thing). Check the ground connection? Make sur that is solid. Also, check the voltage with the car running. Should be getting around 14.5v. Why were you testing it in the first place? Connecting an amp soon? Again, check your ground. But, whatever you do, DO NOT let the two touch again! Sheesh.

 

[focushead]

I am in fact saying that there are no sparks, which to me seems like something that should be happening when that much juice is flowing.

I have checked the ground and it seems fine, in fact I rubbed the remote on lead against it and there are nice little sparks.

Yes, I am getting about 12.5v on my DMM, although I have not yet tested it with the car on which is something I need to do.

To give some more background: I had another amp hooked up which worked generally but the amp was a bit shoddy (bought used) and seemed to have some bad terminals so I purchased a new one. I went to test said amp and it would not power on. At the time I had no testing equipment on hand so I used the spark searching technique to see if perhaps the fuse on the power wire had blown, but there were no sparks.

Now of course in the past I have "accidentally" touched these two wires together and they practically solder themselves together there's so much juice going through them. So when I saw that this was not happening I was very disturbed. I tested it with the DMM and got a voltage reading so I went into shock from being so confused!

I will make sure not to cross the wires again, but can anyone please explain how it is possible that a voltage could be read but there's not enough current (I think) to make a spark.

 

[maylar 10+ year member]

It's possible that your fuse is blown (you DO have a fuse in that wire, right?) and the DMM is picking up leakage current through the fuse holder. This is a long shot but that's all I can think of. Try putting a 12V bulb or test light on it and I'll bet your DMM reads zero.

 

[focushead]

The fuse being blown sounds pretty reasonable. I appreciate all the help, I will get a new fuse as well as take it to the shop if that doesn't solve the problem.

 

[focushead]

Just to clarify, I won't try to spark them without the fuse in there lolz!

 

[jteske88 10+ year member]

Do you have a ****** ground? Paint on area your touching?

 

[focushead]

The ground is fine as far as I can tell. I'm determining that based on the fact that my previous amp worked great, no heat ups or anything like that, aside from its own internal problems. Also, the Remote On from the head produces nice little sparks off of the ground.

The only thing I can think of and what I have heard is that the fuse is bad (and some minor current is passing as someone here mentioned) or possibly there is some corrosion preventing serious flow, although my battery terminals seem clean enough, I will check this out.

 

[JoeK 10+ year member]

The ground is fine as far as I can tell. I'm determining that based on the fact that my previous amp worked great, no heat ups or anything like that, aside from its own internal problems. Also, the Remote On from the head produces nice little sparks off of the ground.
The only thing I can think of and what I have heard is that the fuse is bad (and some minor current is passing as someone here mentioned) or possibly there is some corrosion preventing serious flow, although my battery terminals seem clean enough, I will check this out.

How to blow up your head unit, by focushead ON SHELVES NOW!

 

[av83 10+ year member]

Lmmfao. This is some funny shiz....