Okay, so here's the problem. My buddies head unit won't give out sound. Turns on, reads cd, but no sound.

So, I put my head unit in his car and everything works fine. I told him to come over my house because I have a couple other head units and that I'd give him one.

We get to my house, and I put one of my other ones in his car. Well, it ended up doing the same thing as his. I put his head unit and wires in my car and it worked fine. Put my other head units in my car, and they worked fine. But I can't figure out why only mine, the one in my car, will work in his. Any help would be greatly appreciated.

 

shorted/dead speaker maybe

 

what does he drive?

 

I thought the same thing, but my head unit will work in his car.

He drives CX just like me.

 

there could be short in factory or aftermarket speaker wires depending how its hooked up.
does he have the speakers hooked to an amp or to the deck?

 

The speakers are hooked up to the head unit. But I really don't think that's the problem, considering my head unit will work in his car, but NO other one will. I just told him to buy the same exact head unit I have and see what happens. That's honestly the only thing I can think of right now.

 

How are all these units wired into the cars in question? Hacked?

 

Through an adapter harness. My harness and head unit work in his. His harness and head unit work in mine. I thought maybe it would be his harness, but like I said, it works in mine. I'm just so confused about everything.

 

I have to agree, most likely a short in a speaker lead or speaker, [burnt VC], the protection circuit in all car HUs are not the same some are more sensitive then others,

Try this, connect his cars speakers to his HU one at a time, see what happens.

If it is already wired you can try this, turn HU on, fade all the way to the rear and balance all the way to the left or right, turn off the HU wait a few sec, then turn it on again, if it works, try each speaker by itself untill the unit will not make sound and you have found the bad speaker/wiring.

Also to be sure, make sure the speaker outputs are wired properly, each pos.(+) and neg.(-) output must go to it's respective speaker, crossing even the neg.(-) of a left and right or front and rear speaker will cause the protection circuit to turn off the internal amp.

http://www.installdr.com/Harnesses/HA-Wiring.asp make sure the adapter harness is pinned properly, again just because your HU works in his car does not mean it is not miswired, check it carefully 94

 

I understand what you're saying, and I'll try it. With the speakers at least. But I don't think the harness itself is the problem, I even rewired it just to make sure everything had a good connection. But like I said, I'll try the whole speaker thing and let you know what happens.

 

Did you check the pin positions in the adapter plug to make sure they are in the correct position, I have run into more then a few that were "mis-pinned"? 94

 

Yeah, I checked that and it was good. Like I said though, his adapter worked in my car just not in his, and mine works in his car. I haven't tried the whole speaker thing yet because we've both been working a lot, so we haven't had time to do any of that.