They do do it with the speaker wires, basically there is a circuit built into the feedback circuit of the headunit. It basically monitors the current on each speaker lead (-) and (+). If the current on one lead is slightly different than the current on the opposite lead, due to being grounded or a dead short,the headunit can tell this and goes into "protect". It's more comlicated than that, buttha's basically how it works I've just never seen a model actually tell you it's in protection, usually they just go silent.

 

basically how a resitor acts in a wiring series? I mean i understand that but what is the point of that? I mean unless your totally **** or Have no clue how to wire anything. Oh well... I stand by my Pioneer and Alpine Hu's any day...

 

Pioneer and Alpine do the same thing. The reasopn is, if a speaker is dead shorted, whether it is touching the chassis, the voice coil burnt up, or otherwise, the resistance goes from the normal 4-8 ohms down to nearly 0. Ohm's Law tells us that impedence is inversely proportional to current. So when the impedence goes down, the current increases. The extra current flowthrough the headunits circuitry can easily damage the headunit. So it shut's off the output side of the headunit.

Same idea as putting a sub/speaker on an amp with too low of an impedence. The amp will usually get hot (from he excess current) and go into thermal protection or blow fuses.

 

man i gotta get a new HU then... mine doesnt do that... Old school DEH-P6500 is what im running and I love it to death lol. But soon to be switching over to a new Alpine all digital reciever...

 

Really? it should do it. I wouldnt try it, but it should do it. I even have a 6400mp and a p9300mpthat do it. Love the 9300! Old school Pioneer's kick ***! I'm running a p6700mp in my truck right now, but I think I'm gonna get a 7900BT sometime soon. Who knows...

 

i dont like the 7900BT really that much... i think u would be better suited to have the 880prs premier model... Its much more utilitarian and is less flashy than the 7900BT...

If i could i would try to get a P-DEX9 like this one guy i know... He has a hella nice car though so it kinda fits his application...

66 Dodge Charger R/T 440.... has a great system in it too.

 

Well, guys, y'all were right, I think. I was on the way home yesterday, listening to the subs by themselves (fun) when I hit the mother of all potholes. All of a sudden, all the speakers work again...yea...until I hit the next pothole 30 mins later and back to only the subs working.I am taking it to my shop tonight to rip into it...will post the results tomorrow...I'm really glad the HU is not f*ked...

 

I agree the 7900BT IS flashy, which is my only real reason for not having one right now, but I still like it. Feature wise. The Bluetooth is what I'm after.

 

Well, back at it. I pulled the door pannel and loosened the the speaker. After getting one of the four screws out, I was half way unbolting the second screw andall the door spks came on. Tightened the screws back in, the speaks died again. I took out all the screws and examined the whole deal. There were no conflicts that I could see, soI bolted the speaker back to the door with shorter screws. Everything worked great until today when I hit a potholeand the d*m thing kicked out again. I cannot for the life of me figure out what to do (besides a hammer)or where its shorting. Any help would be muchly appreciated.

 

Check where the wires enter the door boot, also check the boot itself, by wiggling the boot and see if the speakers come on again. These are sharp flex points for the wires and a common place for breaks in the wires. Jeeps are notorious for this, but it happens in other vehicles occasionally too.

Check the terminals on the speakers themselves, make sure none of the terminals or any wire is touching the basket of the speaker. The basket is grounded through the screws that hold it to the door, so if either wire is touching that it would go along with why it worked when you got the speakers out.

Something is obviously loose or touching, and it seems to be in the door area, so check and recheck everything. Worse case, take em all out, and start over. I find that puting everything back to stock again, trying it and checking for the problem, then start adding the aftermaket stuff again is the final option in troubleshooting a problem. If it still does it with everything back to factory, then you know to look at factory wiring, ect, if not, it's obviously something you did.

Good luck and keep us posted!