DIAGNOSIS:
Fixing a broken bose amp
PROCEDURES:
I will do the best I can to explain a possible cheap fix for
the Delco bose amps that has worked for me several times.
First of all I would like everyone to know I have seen
the (T1) as they are called Bose amps for as low as $50.00
new, so if this is not worth your time STOP now and buy new
ones! I cannot recall all of the sources, there are several,
others on the net that should be able to help you with some
leads if not I will dig them up.
I cannot guarantee this will fix all of your amps but I
believe its worth a try, worst case you spend a little time,
about $5.00 in parts and have to buy a new one if it doesn't
work. Best case you fix your amp cheap and have a feeling of
having accomplished something. I have fixed several amps
with the following problems successfully.
1. amp does not play at all.
2. amp plays at much lower volume than the rest.
3. amp squeals.
4. amp cracks hisses or pops intermittently or always.
The tools you will need; a pencil type soldering iron,
solder, small pliers (needle nose) and or tweezers, exacto
knife, solder sucker (not a must but really helps), steady
hand and patience (must).
The parts you will need; a few (usually no more than 6-8
per amp) tiny single axial capacitors (looks like a can with
both leads coming from bottom). You will need to look at
your amp for the specific size and values. They do not have
to be the exact same size (physically) as long as the values
are the same, however they must still be small enough to fit
in the proper spot on the circuit board. The following are
the values I have most commonly needed.
1. 1uF 50V
2. 4.7 uF 35V
3. 10 uF 16V
4. 47 uF 16V
5. 1000uF 16V (this ones a little larger and only needed a
couple of times)
There may be some other values needed depending on the
year and model of your car (coupes and convertibles use
slightly different amps). You will need to look at your amp
module to determine this. You are looking for the tiny green
chrome looking capacitors. They look like little shiny green
cans and usually there are 6 to 8 of them.
The amp modules themselves are located in or on the
speaker enclosures in all four corners of the car. They are
attached to the enclosure with (4) 1/4 inch screws. The
later models have a white quick disconnect at the amp, the
earlier models do not. If you have the earlier models 90 to
93 (I think) do not cut your wires, you can follow the wires
out of the enclosure about 6 to 12 inches to a square black
connector and disconnect it there.
Once you have the amp module out you can easily see the
little green capacitors that are usually the culprit. These
particular ones are known to fail in all kinds of car
stereos, cellular phones, CD players etc. Do not buy the
shiny green ones as replacements, avoid them at all costs.
You will be able to find the capacitors at almost any good
electronics supply store for less than 50 cents a piece,
however I have not had any luck purchasing these from Radio
Shack.
If you hold the amp with the components up, and the
wiring connection to the top you should see the shiny green
capacitors mainly in the center and toward the lower right.
I would replace them all. There are usually at least 2 that
are bad but if you only change some of them you will
probably have to replace the others soon afterward. Most are
easy to get to except for the ones in the center near the 3
large coils with the goop on them. The goop is kinda like a
hot glue they pour on the heavier components to keep them
from breaking off the circuit board. You will have to
carefully cut or melt some of this away to get to the center
capacitors.
By careful heating the leads from the bottom of the board
you can use the pliers or tweezers to pull the component
out.
IMPORTANT make sure to note the black stripe or arrow on
the side of the cap and orient the new one the same way!
When you put the new one in you should need very little
solder if any, so be careful not to glob or drip any extra
onto the circuit board. Try also not to touch or overheat
the chips (these are the ones that say Bose on them) they
are very susceptible to damage from static electricity and
excess heat.
I believe this will fix a lot of your amps. This is
really not as intimidating as it might seem.
One place you can call to fix your amps is:
Tony Hampton
CoastLine Electronics
Specializing in Bose Automotive Amplifiers
