Test L: The Subwoofer Is Inoperative
PINPOINT TEST L: THE SUBWOOFER IS INOPERATIVEL1-L2:
L2-L4:
L5-L6:
Normal Operation
The subwoofer speaker is powered by a separate subwoofer amplifier. Circuit 174 (GY/BK) carries out 2 functions: to turn on the subwoofer amplifier, and to indicate to the audio unit when the subwoofer output distortion signal reaches a damaging level. The audio unit then reduces the audio output signal to the subwoofer amplifier. The subwoofer amplifier receives voltage on circuit 720 (RD/YE) and ground on circuit 694 (BK/LG). Audio signals are received by the subwoofer through circuits 169 (LG/BK) and 172 (LB/RD).
Possible Causes
- Fuse
- Circuit 720 (RD/YE) open
- Circuit 174 (GY/BK) open or short to ground
- Circuit 169 (LG/BK) open, short to voltage, or short to ground
- Circuit 172 (LB/RD) open, short to voltage, or short to ground
- Circuit 694 (BK/LG) open
- Subwoofer amplifier
- Subwoofer
- Audio unit