I was having trouble with CDs skipping on the factory radio in my 94
Trans Am. I pulled the radio out of the car and took it apart,
intending to clean the lens and adjust the tracking (if needed). While
it was apart I decided to check ESR on the electrolytic capacitors. On
the (Sony) CD main control board there are half a dozen 4.7uF @ 6.3v
cap's. The ESR on all of those measured quite high, so I want to
replace them. The problem is that I can not tell which lead is + and
which is -. There is a polarity stripe on one end, but both leads come
out on that end. These look like a black plastic surface mount
tantalum chip except that instead of having a wraparound terminal on
each end, there are 2 wire leads coming out of one end. They are
actually made up of a radial lead aluminum can inserted into a hole
drilled into the cube shaped plastic body. I pulled the can out of the
body on one of them, but there are no markings on the can to indicate
polarity. How can I determine the polarity of the capacitors? The
level of disassembly needed to get at these parts does not lend itself
to powering the unit up and measuring voltage accross the cap's.

Also,
Are there any adjustments on this particular CD transport? I do not
see any pots.

TIA,
Paul