Symptom Chart - Sound Quality

WARNING: This page is about a different car, the 2011 Mercury Milan, 2011 Lincoln MKZ, and 2011 Ford Fusion. However, it is still accessible from the selected car via links, so may be relevant.

SOUND QUALITY

Condition	Possible Sources	Action
Poor reception - AM/FM	Wiring, terminals or connectors AM/FM antenna AM/FM antenna cable Charging system Ignition system Noise suppression equipment Antenna module (MKZ only) Audio Control Module (ACM)	GO to PINPOINT TEST A .
Poor reception - satellite radio	Obstructions to the antenna line of sight Satellite radio antenna Satellite radio antenna cable ACM	GO to PINPOINT TEST B .
Continuous seek/scan - AM/FM	No channel found in the selected category AM/FM antenna AM/FM antenna cable Noise suppression equipment ACM	GO to PINPOINT TEST A .
Continuous seek/scan - satellite radio	No channel found in the selected category Obstructions to the antenna line of sight Satellite radio antenna Satellite radio antenna cable ACM	GO to PINPOINT TEST B .
Poor sound quality/no sound while in satellite radio mode - all other functions operate correctly	Satellite radio antenna Satellite radio antenna cable ACM	GO to PINPOINT TEST B .
Poor quality/distorted/no sound from one or more speakers (not all speakers) - base, mid-level sound	Wiring, terminals or connectors Speaker ACM	GO to PINPOINT TEST C .
Poor quality/distorted/no sound from one or more speakers (not all speakers) - premium sound	Fuse Wiring, terminals or connectors Speaker Audio amplifier Subwoofer amplifier ACM	GO to PINPOINT TEST D .
Poor quality/distorted/no sound from one or more speakers (not all speakers) - Sony® sound	Fuse Wiring, terminals or connectors Speaker Audio Digital Signal Processing (DSP) module ACM	GO to PINPOINT TEST E .
Poor quality/distorted/no sound from one or more speakers (not all speakers) - THX® sound	Fuse Wiring, terminals or connectors Speaker Audio DSP module ACM	GO to PINPOINT TEST F .
Poor quality/distorted/no sound from all speakers	Fuse Wiring, terminals or connectors Audio DSP module (Sony® sound, THX® sound) ACM	GO to PINPOINT TEST G .
Poor quality/distorted/no sound while in SYNC® mode	Wiring, terminals or connectors Accessory Protocol Interface Module (APIM) ACM	GO to PINPOINT TEST H .