Test F: The Subwoofer Is Inoperative/Does Not Operate Correctly - Audiophile

PINPOINT TEST F: THE SUBWOOFER IS INOPERATIVE/DOES NOT OPERATE CORRECTLY - AUDIOPHILE

F1-F2:

F3-F5:

F5-F7:

F7-F10:

Normal Operation
The audio unit sends audio signals to the subwoofer amplifier through circuits 169 (LG/BK) and 172 (LB/RD). The enable/clip circuit 829 (WH/VT) serves 2 functions: to enable the subwoofer amplifier, and to detect an overload condition. When an overload condition is present, the audio unit clips the signal to the subwoofer amplifier (heard as distortion). The subwoofer amplifier receives voltage through circuit 828 (VT/LB), and ground through circuit 694 (BK/LG).

Possible Causes
- Fuse
- Circuit 169 (LG/BK) open, short to ground or voltage
- Circuit 172 (LB/RD) open, short to ground or voltage
- Circuit 694 (BK/LG) open
- Circuit 828 (VT/LB) open
- Circuit 829 (WH/VT) open, short to ground or voltage
- Subwoofer speaker
- Subwoofer amplifier
- Audio unit