Rear speakers not working, where is the amp?
#1
12-20-2009, 02:50 PM
Rear speakers not working, where is the amp?
98 Chevy Blazer 4door, LT package. Came from the factory with the Delco AM/FM radio/single CD in the dash, cassette player in the console, sound system. There are six speakers, one in each corner of the dash, one in each front door, and one in each rear door.
There is a small fade **** on face of radio that allows adjustment of sound from front to rear. When I turn the **** from the detent (center) counter-clockwise, the sound "fades" out and by the time it reaches the stop, there is no sound.
Turn the **** clockwise and the sound comes back and works OK through the full clockwise rotation of the ****.
Previously, the sound would begin to break up or crackle are the fade **** was rotated counter-clockwise.
An auto radio repair shop that I contacted via the internet said the there is a separate amplifier for the rear speakers and that it probably had begun to fail and then had quit working entirely.
Problem is they didn't say where the amplifier for the rear speakers is located!
Anyone have any suggestions of where to look?
There is a small fade **** on face of radio that allows adjustment of sound from front to rear. When I turn the **** from the detent (center) counter-clockwise, the sound "fades" out and by the time it reaches the stop, there is no sound.
Turn the **** clockwise and the sound comes back and works OK through the full clockwise rotation of the ****.
Previously, the sound would begin to break up or crackle are the fade **** was rotated counter-clockwise.
An auto radio repair shop that I contacted via the internet said the there is a separate amplifier for the rear speakers and that it probably had begun to fail and then had quit working entirely.
Problem is they didn't say where the amplifier for the rear speakers is located!
Anyone have any suggestions of where to look?
#2
12-20-2009, 03:01 PM
Unless you have the Bose system (which it doesn't sound like), then all of your speakers are run directly off the deck in the dash (i.e. no additional amplifiers). If that is the case, then your rear speakers are likely blown. It happens. You could test by removing the rear door panels and hooking up a different speaker to the wiring and see if it works.
#3
12-20-2009, 05:17 PM
When I bought my 99 Jimmy both rear speakers and one of the front dash speakers were blown. I just pulled the rear door panel and tested the speakers leads with a known good speaker to confirm my suspicions and then replaced them.
#4
12-21-2009, 07:18 AM
the right rear speaker in my 97 was blown when the truck was purchased, replace and upgrade was needed 
in my 98 which still has the factory radio, the fade **** is iffy, it has been my theory that the radio itself is faulty and not the speakers since when all the settings are centered all speakers work ok, when you start fiddling with the fader is when the sound dissipates from the speakers entirely (when faded to the rear only the left rear works, when faded to the front the non working speaker works ok) the balance works fine though. i think i read somewhere the delco radios are prone to acting goofy
so id say its a toss up, replace the radio and replace the speakers too, neither of my bravadas have Bose equipment so no amp to worry about
in my 98 which still has the factory radio, the fade **** is iffy, it has been my theory that the radio itself is faulty and not the speakers since when all the settings are centered all speakers work ok, when you start fiddling with the fader is when the sound dissipates from the speakers entirely (when faded to the rear only the left rear works, when faded to the front the non working speaker works ok) the balance works fine though. i think i read somewhere the delco radios are prone to acting goofy
so id say its a toss up, replace the radio and replace the speakers too, neither of my bravadas have Bose equipment so no amp to worry about
#5
12-21-2009, 09:54 AM
the right rear speaker in my 97 was blown when the truck was purchased, replace and upgrade was needed
in my 98 which still has the factory radio, the fade **** is iffy, it has been my theory that the radio itself is faulty and not the speakers since when all the settings are centered all speakers work ok, when you start fiddling with the fader is when the sound dissipates from the speakers entirely (when faded to the rear only the left rear works, when faded to the front the non working speaker works ok) the balance works fine though. i think i read somewhere the delco radios are prone to acting goofy
so id say its a toss up, replace the radio and replace the speakers too, neither of my bravadas have Bose equipment so no amp to worry about
in my 98 which still has the factory radio, the fade **** is iffy, it has been my theory that the radio itself is faulty and not the speakers since when all the settings are centered all speakers work ok, when you start fiddling with the fader is when the sound dissipates from the speakers entirely (when faded to the rear only the left rear works, when faded to the front the non working speaker works ok) the balance works fine though. i think i read somewhere the delco radios are prone to acting goofy
so id say its a toss up, replace the radio and replace the speakers too, neither of my bravadas have Bose equipment so no amp to worry about
#6
12-21-2009, 11:58 PM
My rear speakers were 'shot' when I bought my rig too, I would fade to the rear and I would loose all sound. I pulled them out to test them and they worked fine when hooked up to any other source. I replaced them with some Alpines and haven't looked back. Although I'm still not sure why they didnt work... 
#7
12-24-2009, 03:59 PM
My right rear speaker just started not working. I pulled the deck out and checked all wiring even resplicing that rear speaker. Still nothing. Not even a crackle. I thought when they blew they make static. Am I wrong?
#8
12-28-2009, 03:56 PM
One that is producing alot of scratchy/static sounds is probably physically damaged. Meaning the coil is scraping inside the motor, surrond is torn... could be anything, but the end result is a damaged speaker either way.
#9
05-02-2010, 03:13 AM
Your Speakers Arent Blown, i found this out by tinkering, i was playing a burnt cd (from my pc) and noticed i got no sound, but the second i put in a store bought cd, my bravadas speakers suddenly made music again, the result, either the cd's missing a layer of audio, or the rear speakers are passive, and not fully active 100% of the time, i hope this has helped
#10
05-02-2010, 09:29 PM
I always test speakers in two ways. Unless it's a VERY high end subwoofer, if the cone won't move at all or very difficult, you have a problem. If you connect a 9 volt battery to the speaker terminals and the cone doesn't move, it is bad.
A crackle noise or sound cutting in and out with the bass notes could mean that the voice coils are bad like stated above. Or the tinsel leads that run between the speaker terminals to the cone could be loose.
Just my 2 cents.
A crackle noise or sound cutting in and out with the bass notes could mean that the voice coils are bad like stated above. Or the tinsel leads that run between the speaker terminals to the cone could be loose.
Just my 2 cents.