2007 cierra ,my radio cones on but not putting power to speakers except to 1 front speaker and it has almost no sound ,up full and very screechy . do I need a new radio ?

Speakers get power from the amp if your system has one or from the radio , if the tweeters work it's not a fuse problem . You like listen to your stereo loud . Blew a channel in the radio or amp ?
Take it and have it checked for DTC'S - diagnostic trouble codes
DTC B1025 01: Audio Output 1 Left Front Circuit Short to Battery
DTC B1025 02: Audio Output 1 Left Front Circuit Short to Ground
DTC B1035 01: Audio Output 2 Right Front Circuit Short to Battery
DTC B1035 02: Audio Output 2 Right Front Circuit Short to Ground
DTC B1045 01: Audio Output 3 Left Rear Circuit Short to Battery
DTC B1045 02: Audio Output 3 Left Rear Circuit Short to Ground
DTC B1055 01: Audio Output 4 Right Rear Circuit Short to Battery
DTC B1055 02: Audio Output 4 Right Rear Circuit Short to Ground

Each of the audio output channel circuits (+) and (-), at the radio and audio amplifier (if equipped) have a DC bias voltage that is one half of the battery voltage. When using a DMM, each of the audio output channel circuits will measure approximately 6.5 V DC. The audio being played on the system is produced by a varying AC voltage that is centered around the DC bias voltage on the same circuit. The AC voltage is what causes the speaker cone to move and produce sound. This voltage will vary depending on what type of audio is being listened to, talk or music, and type of music, as well as the volume setting of the system. Low volume and talk settings will measure around 1V AC and less, where constant music may measure 3 V AC and slightly higher.
Do you know how to do DC voltage testing ?
Without Amplifier without UK6
Ignition OFF, disconnect the harness connector at the appropriate speaker.
Radio ON, test for 5.0-7.5 V between the signal circuit terminal A and ground.
? If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the radio.
? If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the radio.
Test for 5.0-7.5 V between the signal circuit terminal B and ground.
? If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the radio.
? If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the radio.
If all circuits test normal, replace the speaker.

speakers magnets not getting full power, speakers are shot, wiring from radio to speakers come loose or partially broken, radio not putting out enough power to speakers, controls of radio not set correctly

You have it right. Use a 12 volt test light to see if there is power between the gray and brown wires when the key is on. If there is power there, you may have got hold of a bad radio.


1990 Toyota Celica Car Stereo Radio Wiring Diagram
Radio Constant 12V+ Wire: Blue/Yellow, connects to yellow
Radio Switched 12V+ Wire: Gray, connects to red
Radio Ground Wire: Brown, connects to black
Radio Illumination Wire: Green, do not use
Radio Dimmer Wire: N/A
Radio Power Antenna Trigger Wire: Black/Red
Radio Amplifier Turn On Trigger Wire: N/A
Front Speakers Size: 4? Speakers
Front Speakers Location: Dash
Left Front Speaker Wire (+): Pink
Left Front Speaker Wire (-): Purple
Right Front Speaker Wire (+): Light Green
Right Front Speaker Wire (-): Blue
Rear Speakers Size: 5 1/4? Speakers
Rear Speakers Location: Side Panels
Left Rear Speaker Wire (+): Black
Left Rear Speaker Wire (-): Yellow
Right Rear Speaker Wire (+): Red
Right Rear Speaker Wire (-): White

Sounds like a loose ground. Obtain a good volt/ohm meter and the wiring shop manual for your model and trace out the wires.
You should be able to find and fix the problem.
Sometimes weather will wrinkle the cones in speakers. Check yours, if they are dried and distorted take them to the parts counter guy and get new ones.

I assumed full size truck?


1989 Chevrolet Truck Stereo Radio Wiring Diagram

Car Radio Constant 12v+ Wire: Orange
Car Radio Switched 12v+ Wire: Yellow
Car Radio Ground Wire: Black
Car Radio Illumination Wire: Gray
Left Front Speaker Positive Wire (+): Tan
Left Front Speaker Negative Wire (-): Gray
Right Front Speaker Positive Wire (+): Light Green
Right Front Speaker Negative Wire (-): Dark Green
Left Rear Speaker Positive Wire (+): Brown
Left Rear Speaker Negative Wire (-): Yellow
Right Rear Speaker Positive Wire (+): Dark Blue
Right Rear Speaker Negative Wire (-): Light Blu

1995 Jeep Grand Cherokee Car Stereo Radio Wiring Diagram
Radio Constant 12V+ Wire: Red/White
Radio Switched 12V+ Wire: Red/Gray
Radio Ground Wire: Black
Radio Illumination Wire: Blue/Red
Radio Dimmer Wire: Orange
Radio Power Antenna Trigger Wire: Green/Red
Radio Amplifier Turn On Trigger Wire: N/A
Front Speakers Size: 6 1/2′
Front Speakers Location: Doors
Left Front Speaker Wire (+): Green
Left Front Speaker Wire (-): Brown/Red
Right Front Speaker Wire (+): Purple/Yellow
Right Front Speaker Wire (-): Blue
Rear Speakers Size: 6 1/2′
Rear Speakers Location: Rear Doors
Left Rear Speaker Wire (+): Brown/Yellow
Left Rear Speaker Wire (-): Brown/Light Blue
Right Rear Speaker Wire (+): Blue/White
Right Rear Speaker Wire (-): Blue/Pink

if no sound from both speakers check fuse,
if some hissing or humming on full volume then its a fault in oscilator section
if there is no hiss or hum at full volume its a breakage in the wires of speakers, if one speaker is ok its aagain a wire open problem in out put section
open up the speakers and just apply 1.5 volts dc for fraction of second to the speaker leads , if theres crackling the speaker is ok
also see for torn out cones or stuck cone or speaker coil open.

Here are the radio wire colors of the whole system, please rate this solution.

2007 Pontiac G6 Car Radio Stereo Wiring Diagram
Car Radio Battery Constant 12v+ Wire: Red/White
Car Radio Accessory Switched 12v+ Wire: The radio harness does not provide a switched power source. Run a wire to the fusebox for switched power or use the brown wire (+) at the ignition wire harness.
Car Radio Ground Wire: Black/White
Car Radio Illumination Wire: Pink
Car Stereo Dimmer Wire: N/A
Car Stereo Antenna Trigger: N/A
Car Stereo Amp Trigger Wire: N/A
Car Stereo Amplifier Location: N/A
Car Audio Front Speakers Size: N/A
Car Audio Front Speakers Location: N/A
Left Front Speaker Positive Wire (+): Tan
Left Front Speaker Negative Wire (-): Gray
Right Front Speaker Positive Wire (+): Light Green
Right Front Speaker Negative Wire (-): Dark Green
Car Audio Rear Speakers Size: N/A
Car Audio Rear Speakers Location: N/A
Left Rear Speaker Positive Wire (+): Brown
Left Rear Speaker Negative Wire (-): Yellow
Right Rear Speaker Positive Wire (+): Dark Blue
Right Rear Speaker Negative Wire (-): Light Blue

TEST THE SPEAKERS USING A 9 VOLT BATTERY, USE A JUMPER TO THE SPEAKER TERMINALS, TOUCH ONE LEAD OF THE 9 VOLT BATTERY TO THE SPEAKER AND QUICKLY REMOVE THE POWER, THE SPEAKER CONE WILL JUMP IF THE SPEAKER IS GOOD, IF IT IS THEN THE RADIO NEED TO BE REPAIRED. THIS IS MOST LIKELY A RADIO ISSUE.

MY 2003 Protege radio turned on and displayed correctly but was silent until I discovered that one trunk speaker braided copper "cone wire" was grounding to the speaker frame. Separating the wire restored full sound to the system. Who knew?