Audio System: Inspection: Notes

Symptoms	Repair order
No power coming in. (No display and no sound from speakers)	Check the fuse and power supply for audio. Check the audio ground. Remove the audio for repair.
A specific speaker does not operate.	Check the speaker. Check the output circuit between audio and speaker.
Audio generates noise with engine running.	Check the audio ground. Check the generator. Check the ignition coil. Remove the audio for repair.
Volume is low in AM and FM modes or interference noise occurs.	Check the antenna. Check the audio ground. Remove the audio for repair.

NOTE:

For HD radio, the following symptoms may occur in the nature of radio waves.

Hybrid mode providing both digital broadcasting and analog broadcasting
When the vehicle moves outside the digital broadcasting area (smaller than analog broadcasting area regulated by FCC output specification), the digital voice is automatically switched to the analog voice.
Main channel and sub channel are available in the same frequency. (FM broadcasting only)
Digital voice failure (delay echo skip) may occur due to reasons of broadcasting station. This is not a malfunction of audio unit.
Depending on the broadcasting area, digital spectrum cannot be received even in the area where analog broadcasting can be normally received. Or switching between digital broadcasting and analog broadcasting may frequently occur. These are not malfunction of audio unit.