Really Weird Problem

wang_chi7 · Post by **wang_chi7** » Fri Oct 20, 2006 4:26 pm

I just installed an Alpine CDA-9831 and no sound is coming out of the main speakers. My subs seem to be playing what the mains are supposed to even though the LPF is set at 80 on the sub amp itself. The mains aren't hooked up to an amp, just the head unit. The RCA's are in the correct spot (I double checked), and I'm stumped.

Does anyone have a clue what could be causing the problem?

Is the HU bad? I bought it off of ebay used, but from a very highly rated seller. I figured I'd better make sure it wasn't me before writing a nasty message to them!

Justin from Detroit1 · Fri Oct 20, 2006 4:29 pm

Does that HU have the option to turn the internal amplifier off? If so, that would cause the main speakers not to play.

wang_chi7 · Post by **wang_chi7** » Fri Oct 20, 2006 4:37 pm

Yeah it does. I have the internal amp turned on.

Scarrell · Post by **Scarrell** » Fri Oct 20, 2006 8:10 pm

this may be dumb.. but did you hook the speakers up to the hu? or leave them on the stock amp in the car?

elevation101 · Post by **elevation101** » Sat Oct 21, 2006 4:57 am

What kind of car is it? Are the speakers factory or aftermarket?

wang_chi7 · Post by **wang_chi7** » Sat Oct 21, 2006 5:53 am

The car is a 2001 Chevy Impala. There is no stock amplifier to bypass, and yes the speakers are hooked up. The speakers are aftermarkets and worked with my older aftermarket HU.

solacedagony · Post by **solacedagony** » Sat Oct 21, 2006 6:51 am

You could test the speaker leads to see if voltage is coming through or not. Maybe one of the wires is grounding out.

cargodz · Post by **cargodz** » Sat Oct 21, 2006 7:02 am

Double check everything from your install behind the dash... any wire grounding out and or crossed can cause some big headaches.

elevation101 · Post by **elevation101** » Sat Oct 21, 2006 6:56 pm

One of your stock speakers may have a funky impedance. Most aftermarket decks will shut off the internal amp to all the speakers if one is coming back with a bad impedance. Stock decks dont have that feature and may play fine but I've run across the same problem your having at least a dozen times over the last couple years. Disconnect one speaker at a time and see if it starts working.

geolemon · Post by **geolemon** » Sun Oct 22, 2006 10:47 am

wang_chi7 wrote:The car is a 2001 Chevy Impala. There is no stock amplifier to bypass, and yes the speakers are hooked up. The speakers are aftermarkets and worked with my older aftermarket HU.

The install that I did on a Chevy Impala (I believe in fact, that it may have been a 2001 model) used a wiring harness adapter that provided a long length of harness to keep the factory HU "in the circuit" (I relocated that one in the trunk - they give you plenty of harness length).

They do make other wire harness adapter solutions - essentially you are buying a "black box" that contains all the circuitry that needs to be retained in the HU you are replacing.

So the question is - can you provide the make and model number for the HU wire harness adapter that you used when you hooked that HU up into your car?

Of course, I am making the leap of faith here that you didn't perform the #1 ESTBAAIC (Evil Sin To Be Avoid At All Costs) of cutting factory car wiring [such as some hillbillies do - cut the factory harness plug right out - to "hard wire" the new head unit in

]?

As far as I know (granted the car I worked on was the supercharged top-end model Impala), all Impalas fall into this category... so you may be understanding your situation incorrectly.