I got a car stereo ? for ya....

I was installing a car stereo in a friend honda accord....roughly a 97...its all wired up properly but will not play sound.......if i turn the radio off then turn it back on with the FM radio on and no attena hooked up it will play static through the speakers......as soon as I wire the antenna the sound cuts off..the power to the cd player never goes off..same with the cd player.....First thing i thought was maybe honda had amps seperate for the speakers and the factory radio itself didnt have a wattage output....

but i dont see anything that resembles an amp with the speakers......

any insight? something you have encountered before?

 

Is the head unit new or used? If it is used, have it bench tested before installing it. I want to say that this sounds like a grounding problem, because the antenna hook up will provide ground, but not reliable. Try hooking the ground wire from the head unit directly to a metal part of the chassis. Also be aware that Honda cars beginning in '97 started running the remote keyless entry through the head unit, and you need to use the proper wiring harness to make it all work. Metra or PAC should have the one you need if this is the case.

One sure way to tell if a car has a factory amp is to pop the speakers with a 9 volt battery with the ignition off. If they pop, no factory amp.

 

Most likly a bad antenna ground. Try that and get back to us if it still wont work.

-Matt

 

it can be the ground of the radio even if the radio powers up fine but sound wont be outputed?

It does the same thing with a diff radio i know works so it is something with the ground......the factory radio works fine with the ground...

Is it possible the ground just isnt good enought for a aftermarket radio but will provide adequite ground for the factory radio?

Also....what part of the speaker do u touch the 9volt battery to? the power terminal?

thanks...........

 

What's it do when you pop a cd in? Still no sound?

 

same thing as when i hook up the antenna....it may do a little burst of sound for a half second then turn off.....then i switch it to FM radio, power it off and pulll the antenna and when it comes on again it will play static.......

over and over...same thing for both decks i got

 

Identify the speaker wire pairs, and then simply touch one wire to one post of the battery, and the other wire to the other post. The speaker will make an audible pop.

You need to get the head unit bench tested first, or you are running in circles. When I was installing, I wouldn't even turn a screw on a car without testing used equipment fully. Hook it directly to the vehicles battery, and use a test speaker to do this yourself. Be sure to hook up an antenna too, and see if it all works. If it does, then proceed as follows.

You first need to find constant +12v, this is usually the yellow wire on most head units. Use a VOM, this wire in the car will show +12v no matter what position the key is in. Next, find switched +12v, this is usually the red wire on the head unit. In the car, it will show +12v only with the key in the accessory position, or on. Next find a good ground, and be sure to turn the head lights on while doing this to assure you don't have a dimmer circuit, which will show ground when the lights are off. Make sure none of the speaker wires are touching each other, and turn the unit on to see if it works. Plug in the antenna, and use a test speaker to check each speaker output. Next, hook up speakers one by one.

Troubleshooting no sound problems is more of a game of finding out what the problem is not. If you know you have a working unit, properly hooked up to power and ground, then it can only be speakers or the antenna circuit.

 

I think one of your speakers is shorted. If you have a volt/ohm meter, unhook the speaker wires from the deck and do an ohm check and verify that you have 4 ohms impedance, then do an ohm check between 1 wire and chassis ground and make sure that you have an infinite impedance.

 

When checking the ohms of the speaker i just power to power part of meter and ground to ground part of meter correct?

when doin the ohm check between one wire and the chassis i assume i am putting the ground part of the meter directly to they chassis and the power part to the power of each of the speakers?

thanks for all your help guys

 

I Think Jim is on to something. To clarify, if you are using a digital meter, set the dial to ohms, and touch one probe to the speaker +wire, and one to the - wire, it doesn't matter which one you get. If the meter reads about 4 ohms, things are good, if the display reads OL or well below 4.0, you probably have either a short in the speaker wires, or a melted voice coil. Both situations will cause the head unit to go into protection mode, and produce no sound. Doing an impedance check for each wire is useful only to identify which wire is grounded to the chassis. Once you have identified a problem, it is often easier to just run another set of speaker wires rather than try to repair the factory ones.

If you find a problem, I would first pull the speaker in question and test it. If it works, then you know it is the wiring at fault. Take your time, and identify what the problem is not. Think it out.

 

his rear speakers dont work and I havent looked into that yet as to why......when the factory radio is installed it will play out of the front speakers.....

is it possible that the fronts could be bad and wont work with the aftermarket radio and will with the factory one?

or is it more likely that the rears are bad and cause a problem with the aftermarket radio but not the factory one?

i'll try testing all the speakers today.....thanks for the input guys.......

 

In addition to doing an ohm check over the speaker wires, it's also important to do it from 1 wire to chassis ground. If one of the speaker terminals is shorted to ground, the speaker wire test will still show a 4 ohm impedance, but will cause all sorts of problems when applying power. By testing for continuity between the speaker and chassis, you eliminate that possibility. If you get zero ohms (That's a LOT different than infinite ohms), or 4 ohms between 1 speaker wire and chaissis ground, then you have a short.

 

so to do that i just take the positive prong of the meter to each + wire or both the + amd -? and i assume the black one goes to any metal part of the chasis....what should i read if everything is ok?

 

When you use a typical DMM to measure a speaker, aren't you measuring the DC resistance of the coil, not the impendence of the speaker? If so, shouldn't it read closer to or a little above 3 ohms? Just a thought.

- Mike

 

You would think, but almost any speaker I've tested shows a 4 ohm impedance when I use a DMM. There shouldn't be a J-term with a DC voltage, but I'd be surprised if all the speakers I tested had a 4 ohm dc resistance.

Gen X, I'd probably suggest that you buy a book from Sears or Radio Shack on how to use a DMM. It's basic knowledge that you need to have if you want to sucessfully troubleshoot anything with a DMM.

 

I had a similar problem in an mazda when installing an explode. After bench testing the HU and checking some other stuff i realized when the trunk was shut a rod was touching the speakers and grounding it out which would make my sound go away. but it wasnt constant i had a cheap sub box (first car) that would hold the bar away from the speaker so it would work perfect but go around a corner and box moves no sound again. So check out all the wires and make sure nothing is grounding the speaker wire