Radio problem have the am/fm/cd radio that keeps blinking off and on and I can not set the time. The radio works but sounds like the speaker system wiring is also messed up, when you adjust balance to front left it sounds like both back speakers are on. when you adjust to right you only get right side speakers

Do you have base or up;level system ?

Table 1: Radio Features
Table 2: Cassette Features
Table 3: Compact Disc Features
Table 4: XM Advisory Messages
The radio receives power from the RADIO fuse in the junction block-right I/P. Ground is provided via G201 and G202. The radio is enabled/disabled by class 2 messages from the body control module (BCM). The radio routes audio signals from the digital radio receiver or the vehicle communication interface module (VCIM) to the speakers and/or amplifier when directed by class 2 messages.
The Entertainment System on this vehicle is configured with an AM/FM stereo radio with the radio data system (RDS) and either a cassette player or a CD player or both. CD and cassette. The uplevel system provides the customer with extended range speakers and an audio amplifier. Satellite digital radio (U2K) is available with uplevel systems.
The following list shows the radios available for this vehicle:
• Radio (ULO) - AM/FM Stereo, Cassette with RDS
• Radio (UNO) - AM/FM Stereo, CD and RDS
• Radio (UPO) - AM/FM Stereo, Cassette with CD and RDS .The complexity of the radio systems on these vehicle is mind blowing .

Your best bet take it to a GM dealer , has features you are unawear of .
DTC B1025, B1035, B1045, or B1055
When the radio is powered up, the radio supplies low level audio signals to the speakers. If the vehicle is equipped with an audio amplifier, the amplifier will boost the signal sent to the speakers.
DTC B1025 Audio Output Circuit
Install a scan tool.
Turn ON the ignition, with the engine OFF.
With the scan tool, monitor the DTC Information for DTC B1025.
Does the scan tool indicate that DTC B1025 is current?

Maybe a shorted speaker causing the power amplifier inside the radio to shut down or a speaker wire shorted to chassis and last the internal amplifier of the radio cd set faulty by itself... set volume to zero power it off take out the radio cd set; remove the speaker iso plug leaving the power plug only in and power it on if necesary turn again the volume down to zero and wait if it keeps turned on it a speaker problem if it shut itself off again then you go for a repair or a new one

Do you have preminum sound?

Turn on the radio and increase the volume if you can hear a hiss through the speakers, chance is the aerial/antenna connection is not hooked up correctly. Another way to check is try tuning to an AM station if you get a signal on AM but not FM then it is The antenna. You may have to remove the radio to get at the connection.

you must test the power supply faulty a) by rizo , filter, diode, resistor. b) block from DAC, buffer, TRAnsistors, c) speakers some of them faulty or cracking.
se the diagram attached

You should be seeing BCM trouble codes (DTCs) for the radio with a code reader. I am assuming you are hearing something (noise) from the speakers with the radio on. If so, you may have lost the programming in the radio - you could try re-flashing it. However, that radio has a number of memory locations that are set whenever the radio is turned on - one or more memory modules in the radio may now be faulty.

Have you check the mute mode, maybe it is in mute mode.

Try this, put the key in the ignition and let it be on the first turn right marked "ACC" or you can turn off the stereo and you will notice that only the Digital Clock screen will show. Turn the Volume/Audio/Sel knob and press on the "DISP" button simultaneously for about 4 seconds then release the "DISP" button. The digital clock will start blinking, and then use the Tune/Seek arrows pointing up and down to change the time. If the hour digit is blinking change the hour and after you have changed it press "DISP" then the minute digit will start to blink change it using the arrows, when you are done press "DISP" again or leave the clock for between 4 to 8 seconds the clock will start working normally.

I hope this works for you.

Good luck!

Aquinas

Check fuse no. 18(20 amp) in the under dash fuse panel. This is the fuse that keeps power to radio at all times to keep memory alive.

generally each speaker in any car as a wattage range from 25 to at least 60 so if your car as four speakers lets say you would need a radio that with the four speajer channels with 200 watts but 300 would be better because it will move the factory speakers better and it wont put a load on the new radio