1.CHECK FUSE Check for blown fuses.

Power source | Fuse No.
Battery | 8

Is the inspection result normal?
YES>>GO TO 2.
NO>>Be sure to eliminate cause of malfunction before installing new fuse.
2.CHECK POWER SUPPLY CIRCUIT
Check voltage between BOSE amp. harness connector and ground.

Signal name | Connector No. | Terminal No. | Ignition switch position | Voltage (Approx.)
Battery power supply | B16 | 11 | OFF | Battery voltage

Is the inspection result normal?
YES>>GO TO 3.
NO>>Check harness between BOSE amp. and fuse.
3.CHECK GROUND CIRCUIT

1. Turn ignition switch OFF.
2. Disconnect BOSE amp. connector.
3. Check continuity between BOSE amp. harness connector and ground.

   Signal name | Connector No. | Terminal No. | Ignition switch position | Continuity
   Ground | B16 | 12 | OFF | Existed

Is the inspection result normal?
YES>>INSPECTION END
NO>>Repair harness or connector.