No sound from rear speakers in 2005 Chevy Malibu

Check for loose, disconnected, or broken wires, blown fuse, or an open voice coil

Assuming the radio has an output for rear speakers and it is connected to them and you have selected the front/rear fader and attempted to adjust it to the rear, you can't do much more without removing the radio and checking the connections and the wiring to the rear speakers.

When I am faced with this problem I disconnect the speaker wiring from the radio and using a 9 volt battery and two lengths of wire I test the speakers and the wiring by connecting to each speaker in turn. A good speaker with good wiring will produce noise when the 9 volt battery is touched to the terminals. If there is no noise the speaker or the wiring is defective.
If all tests ok then the radio is probably faulty. This can further be tested by connecting temporarily to alternative speakers.

check and adjust the fader control or fix the balance

buy a noise suppressor, you can get it at any audio store

Normal thickness for the fronts 1.023, min machining thickness .906, Discard at or under.898.
Normal thickness for the rear.551, min maching thickness .472, Discard at or under .465
Front: Rear:

front wheel drive , please leave feedback

Sounds like you might need a new switch in the steering column for the turn arm

check wiring on passengers side near the rear hatch speaker, the rear door speakers are run through them also. i had the same problem and it was a unplugged connector at that location

here is a diagram of the radsio connector wire colors in your car, just match them up to your Sony.
1998 Chevrolet Malibu Car Stereo Wiring Diagram
Car Radio Battery Constant 12v+ Wire: Orange
Car Radio Accessory Switched 12v+ Wire: Yellow
Car Radio Ground Wire: Black
Car Radio Illumination Wire: Gray
Car Stereo Dimmer Wire: Brown
Car Stereo Antenna Trigger Wire: Pink
Car Stereo Amp Trigger Wire: N/A
Car Stereo Amplifier Location: N/A
Car Audio Front Speakers Size: 4′ x 6′
Car Audio Front Speakers Location: Doors
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: 6′ x 9′
Car Audio Rear Speakers Location: Rear Deck
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
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