Audio Systems: 1996 Mark Viii car radio with jbl premium + 10cd unit, volume control knob, little buzz


Question
QUESTION: I just bought this car and the cd player was working well as well as radio. I sent it in for some work and now the radio doesn't function. I was told I could leave it on for several hours to get a C to appear on the readout so I could enter a code but the C does not appear.

When I turn it on I can hear some noise in the amplifier but radio does not light up, antenna does not raise, etc.

I suspect loose or broken connection unless the radio was damaged. Is there a block diagram available which would show me the connections from battery power leads to radio, to power amp (where is it, under the rear deck passenger side?) and to speakers?

The cd player was working well before this.

Nothing comes out now. Except a little buzz when I turn the unit volume control knob to on.

ANSWER: I believe they jump start the vehicle or they let the battery die
there is a big amplifier in the trunk,right side of the rear deck this unit   got damage most likely the radio is ok

there is no C or code in this vehicles

---------- FOLLOW-UP ----------

QUESTION: By what method can I test each part of the system? I'd like to test the radio and see if I can get the screen to light up. I'd also like to test the amplifier to figure out what is wrong with it. I have a little audio experience, but not with this type of equipment.

ANSWER: you can not test the radio you don't have a radio
if you are talking about the unit at front, the power comes from the amplifier in the trunk can not be test in pieces


---------- FOLLOW-UP ----------

QUESTION: which wires would I test to see if I can get the amplifier working and how would I know if it is transmitting power to the radio unit?

Are you saying the amplifer is fried because they jump started the car? Is this a common occurrance with the jbl systems? Is there a fuse which may be burned out, and if so, where in the amplifier is it located. How does one get the amplifier down out of the back deck?

Answer
the amplifier is hold with 4 screws from the rear deck
the only way to test is out of the vehicle and with electronic testers to check the power suply inside the board
now this is the case only on the jbl DSP premium sound

there are 3 fuses in the factory fuse box