Subwoofer Circuit Check

Subwoofer Circuit Check

Description

The audio unit sends audio signals to the audio amplifier The audio amplifier amplifies the audio signals before sending them to the subwoofer using the audio signal circuits.

Diagnosis Procedure

Regarding Wiring Diagram information, refer to [Premium Audio System: Wiring Diagram [Crew Cab] Premium Audio System [Crew Cab] ].

1. CONNECTOR CHECK

Check the audio unit, audio amplifier and subwoofer connectors for the following:
- Proper connection
- Damage
- Disconnected or loose terminals

Is the inspection result normal?
YES
GO TO 2.
NO
Repair the terminal and connector.

2. SPEAKER HARNESS CHECK

1 Disconnect audio amplifier connector B158 and subwoofer connector B72.





2 Check continuity between audio amplifier harness connector B158 (A) and subwoofer harness connector B72 (B).






3 Check continuity between audio amplifier harness connector B158 (A) and ground.






Are the continuity test results as specified?
YES
GO TO 3
NO
- Check connector housings for disconnected or loose terminals.
- Repair or replace harness or connector.

3. SPEAKER SIGNAL CHECK

1 Connect audio amplifier connector B158 and subwoofer connector B72.





2 Turn ignition switch to ACC.
3 Push audio unit "POWER" switch.
4 Check the signal between audio amplifier harness connector B158 terminals with SDT or oscilloscope.






Is the audio signal voltage as specified?
YES
Replace subwoofer. Refer to [Subwoofer: Removal and Installation] Subwoofer.
NO
GO TO 4

4. PRE-AUDIO AMPLIFIER HARNESS CHECK

1 Disconnect audio unit connector M66 and audio amplifier connector B159.





2 Check continuity between audio unit harness connector M66 (A) and audio amplifier harness connector B159 (B).






3 Check continuity between audio unit harness connector M66 (A) and ground.






Are the continuity test results as specified?
YES
GO TO 5
NO
- Check connector housings for disconnected or loose terminals.
- Repair or replace harness or connector.

5. PRE-AUDIO AMPLIFIER SIGNAL CHECK

1 Connect audio unit connector M66 and audio amplifier connector B159.





2 Turn ignition switch to ACC.
3 Push audio unit "POWER" switch.
4 Check the signal between audio unit harness connector M66 terminals with SDT or oscilloscope.






Is the audio signal voltage reading as specified?
YES
Replace audio amplifier Refer to [Audio AMP: Removal and Installation] Service and Repair.
NO
Replace audio unit. Refer to [Audio Unit: Removal and Installation] Audio Unit.