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.n


NO - Go to 2.


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

Does it change?


YES - Faulty audio unit.n


NO - Go to 3.


3.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 kW Continuity absent.R = infinity Continuity presentR = about 1 kW 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.n


NO - Faulty front printed circuit board.n