Stereo with no sound questions...

[iroccopz28]

Hi folks, I have been reading a lot of forums where there are stereos working with no sound and I am in the same boat. However most of what I keep reading are with amps being bypassed and I'm not seeing quite whats happening with mine I don't think but I also have some curious questions that maybe dumb questions but I need to ask before I start tearing into anything.

Its a 1993 with what I was told is the JBL sound system. It had an aftermarket stereo in it that was working and then when the ipod was plugged into it one day it quit getting sound which made me think it was the head unit failed so I replaced it with another one that I had that I know works and still no sound. The fuses are good under the food and in the interior fuse panel so I am assuming it has something to do with the amp but I don't know how to test the amp to know if that is the problem.

so here are my questions I guess...

is there a fuse in the factory amp like there is with aftermarket amps that could be bad?

I know it was working before but just out of curiosity is there a specific wire that should be hooked up that I'm not seeing that turns the amp on that might not be working properly?

is it common for the amp to just quit like that? and is the only option to replace the amp? I have been seeing that some people have been getting amp bypass harnesses but seems like a lot of people are having trouble getting them to work as well so I am just frustrated at the moment and could use some advice where to start...

Thank you for any help in advance..

 

[chris2523]

yes there is an amp turn on wire. usually blue in the aftermarket harness.
yes its common for the amps to die.
no the amp bypass does not work.
i generally just remove all of the factory stereo equipment and run a new aftermarket setup.

 

[tixer]

Just popping in to agree with Chris.

If you find that you do have power on that amplifier turn-on lead, I'd take any old extra speaker you have around, and tie it directly on to one of the outputs on the back of your head unit. I'm guessing it'll work fine. The nice thing is, most modern head units push pretty good power.

Then it's just a matter of stringing some new wires.

It is possible to bypass the factory amp, but you'll need a shop manual, lots of time, and probably some external crossovers if you are still running the original separate speakers. It's work, for sure.

Stringing new, fresh wire, is the best way to know you've done it right.

 

[iroccopz28]

Awesome, thank you for the reply's. I found the blue wire, I have a blue wire and a blue with white stripe... the blue one when I connect that one the antenna functions and when I connect the blue with white, I hear the speakers make a light pop noise. So I am assuming that means it is the amp not functioning properly. I have done a lot of stereo work over the years in my own and other vehicle, however this is only the 2nd one that I have done that has had the factory amp setup and the 1st one that I have had issues with so I really do appreciate the advice and help with this issue.

 

[tixer]

No problem at all

Best of luck with the troubleshooting, and feel free to keep us posted. This is the kind of knowledge we like to have posted here for all to see. All of these amplifiers are getting old now, so I expect more and more will experience failures.

Also, Welcome!!

 

[Jamesvinar]

I didnt do my radio but im assuming the aftermarket radio install is simiar to the one i did in my p71. I would inspect the harness and make sure everythings clean and connected properly, i got the orange and red wires mixed up(faded to look the same) and it caused mine to not work

 

[iroccopz28]

here are a couple pictures of what I have when I take the panel down for the amp. The amp has a blue wire going to it that is by itself and I'm not sure what that is?

Also I am curious if anyone would know where I could find a diagram for the inputs and outputs on this amp.

the numbers on it are... F3LF-18C807-DA, I know its hard to read in the pictures but it was the best I could do at that moment.

Also the other wires that are running on that panel that aren't going right to the amp, do they have anything to do with the sound? I don't think they do but I thought I should ask incase I am wrong.

Thank you again, you have all been great.

 

[iroccopz28]

I have learned that the blue wire I was curious about is the wire bringing the signal back to the amp... I wanted to try to splice that wire to the speakers directly but I can't seem to find the wiring diagram that tells me which color is which so I think I am goin to end up running new wire anyways...

 

[iroccopz28]

So after trying a few ideas I had I ended up giving up and running new speaker wires from the HU to the factory speakers. I think I will eventually put new speakers in but for now I think this will work for me. Thank you again for the help that was provided. I know I will be posting and reading more posts to learn more about this car. There are some cool option I like about it and some that need to learn.

 

[tixer]

Sorry we couldn't come up with a "quick fix" for you, but I think you're on the right track. When you just don't know where to start, starting from scratch always works.

Assuming your car still has separate tweeters, you may want to come up with a rudimentary crossover to install between the woofer and tweeter. (really, an appropriately sized, non polarized capacitor in-line with the tweeter will get the job done nicely.)

Without that, you'll be considering aftermarket speakers much, much sooner...

 

[iroccopz28]

I am actually thinking about a speaker overhaul this winter possibly whil eits parked because I don't plan on driving this car in the winter. I have been looking at 2 and 3 way speakers and I am curious if there is a real noticeable difference between them.

When you say an appropriate sized non polarized capacitor, how do I know what the appropriate size would be? Id be willing to try something like that temporarily until I get the new speakers this winter. Right now I have the tweeters disconnected but would like to have them hooked if possible.

Thank you again for all the replies and help.

 

[tixer]

I'm a pretty firm believer that on a quality speaker, more "ways" is better. Each size being best suited to reproduce a specific range of frequencies. I have some speakers at home that prove this isn't always the case, however.

As for the capacitors, I've found calculators on-line before. Usually you'll have to know your desired cut-off frequency, and the impedance of the speaker in question.

Something like this: http://www.v-cap.com/speaker-crossover-calculator.php

If you don't have a lot of experience with these things, this is a great first project. Don't be intimidated. If you hate the final sound, just swap out the caps for different ones. It'll sound better than going without tweeters, no matter what.

A good source for the caps is Parts Express. Don't be swayed into buying the expensive "audio grade" capacitors though. They just aren't necessary for this. Non-polarized Electrolytic is the way to go.

If I can find it, I was bored a few years back and made a plywood "boom box" out of a set of OEM mark speakers, stereo, and and a battery. I did this very thing. I sure don't remember now what caps I used though..

 

[iroccopz28]

Thank you for that link. I am not quite sure how to use it yet or what values I need to enter at the moment but I am planning on looking into it an learning what to do. I am always interested in learning something new even if its something I only use for a short period of time Sorry it has taken me so long to reply to this, my laptop crashed and my ipad wouldn't let me post for some reason but I have a desktop computer working temporarily until I get everything back in order again.

Thank you again...