When radio is turned on, no sound is given - 2004 Mazda 3

I recently tried the DIY service and repair manuals from a website and it actually helped me repair transmission problem in my jcb 3cx site-master. It would'nt move forward or reverse, engine was good both solenoids for
forward and reverse worked, but still couldn't diagnose the problem.
I don't have much technical knowledge but I just followed it step-wise, and now it works perfect! covers wiring, diagrams, torque specs, PCV, everything
got it from www.reliable-store.com

Be absolutely certain that you understand the actual use of each and every wire leading to the stock radio before mating them [in a bridged fashion] to the new harness for the replacement radio. The actual use must be the same for each wire to be adapted from old to new. If different descriptions are given between OEM and replacement for given wire usage, consult someone more knowledgeable before connecting them together.

It does sound as if there is a short in the wiring harness going to the radio.
I would go to your local Advance Auto and ask them to read the actual code given by the service engine light. But the fuse box is located to the left of the instrument panel on the very side of the dashboard. there is a little plastic clip that turns to release the cover panel to show the fuse box on the side of the dash board. and there is also another fuse box located on the drivers side of the engine compartment.

The bcm controls that device for the addition of features like blue tooth and hands free, on-star etc.

IF the speakers are in the doors then the wiring harness in the door-jam is frayed, and you must cut the rubber to access the wires between the door and the door jam to get at the wires without taking the door apart.

Given the intermittent issue, this sounds like a faulty electrical connection. Typically the clock and radio will reset when the battery is disconnected, or they lose power through the fuse. I'd check the power lock and radio fuses to make sure they are intact, and even if they are, try replacing them with spares. If that fails, it may take an automotive electrician to track down the faulty connection.

THE DEAD BATTERY HAS LOCKEED OUT THE RADIO. YOU WERE GIVEN THE RESET CODE WITH THE NEW CAR PAPERWORK.

Turn radio on and unplug speakers one at a time until you hear sound one of your speakers is blown and when it shorts it does something to the sound and cuts totally out..once u find the bad speaker and un plug or replace it will work

check the radio fuse first ,, if its an aftermarket radio, check the wiring behind the unit, they usually add an inline fuse to the set up and installation

1. CODE ENTRY: The proper five digit code for the radio is listed on the two cards supplied in the radio security envelope. After installation or when the radio requires reprogramming the word "code" will appear on the display screen. Enter the code by using the preset buttons numbered 1 through 5 . If a "beep" sound occurs when the code is initially entered, it is then necessary to re-enter the code starting with the first digit. The "beep" sound was provided to indicate the starting point for code entry. If the code has not been properly entered after three successive attempts , the radio will then not accept any entry until the radio has been left "ON" for one hour (vehicle ignition must be "ON"). After one hour in the "ON" position, the radio will then accept three additional entry attempts. Also, if a push-button is touched accidentally when the ignition is "OFF", a warning tone will sound. Turn the ignition to the "ON" position and the warning tone will stop.
2. Radio security codes will not be given to anyone under any circumstance other than authorized jaguar dealer personnel after proof of vehicle ownership and proper identification has been established. A separate security envelope with the attached instruction is provided in each radio package. If the radio has been port installed, the security package will be placed in the vehicle glove box. NOTE: When the car arrives at the dealership, the radio will be in the inoperative mode even though it has already been installed. It is imperative that no attempts be made to install a tape cassette while the radio is in this mode. The cassette will not eject and damage may occur when removal is attempted.