Test G: The Subwoofer Is Inoperative - Navigation Audio Unit Only

PINPOINT TEST G: THE SUBWOOFER IS INOPERATIVE - NAVIGATION AUDIO UNIT ONLY

G1-G4:

G4-G6:

G6-G8:

G8-G9:

G9-G10:

Normal Operation
The subwoofer speakers are powered from a separate subwoofer amplifier. The clip detection circuit, 7-MD19 (YE/RD), 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.

Possible Causes
- subwoofer amplifier
- subwoofer speaker(s)
- audio unit
- circuit 1-MD19 (WH/RD) open or short to ground
- circuit 2-MD19 (GY/RD) open or short to ground
- circuit 7-MD19 (YE/RD) open or short to ground
- circuit 8-MD21 (WH/BU) open or short to ground
- circuit 8-MD22 (WH/GN) open or short to ground
- circuit 10-MD21 (GY/VT) open or short to ground
- circuit 10-MD22 (GY/OG) open or short to ground
- circuit 30-MD19A (RD/YE) open or short to ground
- circuit 31-MD19A (BK) open