Audio System Symptom Troubleshooting - Volume does not change

Volume does not change NOTE: Set the fader and balance position to the center.

1. Operate the volume switch to see if the volume changes accordingly.

Does it change?

YES | - | Operation is normal.■
NO | - | Go to Step 2 .

1. Operate the volume switch to see if the LCD display changes accordingly.

Does it change?

YES | - | Faulty audio unit.■
NO | - | Go to Step 3 .

1. Remove the audio-HVAC display module from the dashboard, and remove the audio unit , and check for continuity between the No. 5 and No. 1 terminals and No. 10 and No. 1 terminals of the printed circuit board 10P connector.

VOL SWITCH | Normal position | 1 Click Clockwise | 1 Click Clockwise | 1 Click Clockwise
--- | --- | --- | --- | ---
Normal | Continuity present. R = about 1 kΩ | Continuity absent. R = infinity | Continuity present. R = about 1 kΩ | Continuity absent. R = infinity
Abnormal | Continuity present | Continuity present | Continuity present | Continuity present
Abnormal | Continuity absent | Continuity absent | Continuity absent | Continuity absent

Check to see if the continuity between the No. 5 and No. 1 terminals will turn on and off as described above when turning the volume clockwise by one click at a time; does the presence and absence of continuity alter?

YES | - | Faulty audio unit.■
NO | - | Faulty front printed circuit board.■