Toyota Tundra Service Manual: No Sound can be Heard from Speakers

PROCEDURE

1.	CHECK RADIO AND DISPLAY RECEIVER ASSEMBLY

(a) In sound output setting mode, set volume, fader and balance to the initial values and check that the sound is normal.

OK:

Audio and visual system returns to normal.

END (SETTINGS ARE DEFECTIVE)

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

Toyota Tundra Service Manual > Touch Select 2-4 And High-low System: Automatic Disconnecting Differential Motor Limit Switch Circuit (P17A4)
DESCRIPTION When the A.D.D. actuator is switching between 2WD and 4WD, the DL1 and DL2 terminals of the limit switch are in one of the ON/OFF combinations listed in the table below. Terminal In 2WD Switching between 2WD and 4WD In 4WD DL1 OFF (OPEN) ON (GND) ON (GND) DL2 ON (GND) ON (GND) OFF (OPEN) ...

Toyota Tundra Owners Manual