Toyota Tundra. Manual — part 158

OK: Your voice can be heard correctly.

NG: REPLACE CELLULAR PHONE

OK: Go to Next Step

2. CHECK SETTINGS

a. Check if mute is set to ON.

OK: Mute is not set to ON.

NG: TURN MUTE OFF

OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS
TABLE (see PROBLEM SYMPTOMS TABLE )

VEHICLE SPEED SIGNAL CIRCUIT BETWEEN RADIO RECEIVER AND COMBINATION
METER

DESCRIPTION

This circuit is necessary for the ASL (Auto Sound Leveliser) built into the radio receiver.

Speed signals are received from the combination meter and used for the ASL.

The ASL function automatically adjusts the sound data in order to enable the driver to hear clear audio sound
even when vehicle noise increases (as vehicle noise increases, the volume is turned up, etc.).

HINT:



A voltage of 12 V or 5 V is output from each ECU and then input to the combination meter. The signal is
changed to a pulse signal at the transistor in the combination meter. Each ECU controls the respective
system based on the pulse signal.



If a short occurs in an ECU, all systems in the diagram below will not operate normally.

WIRING DIAGRAM

2009 Toyota Tundra

2009 ACCESSORIES AND EQUIPMENT Audio/Visual - Tundra

Fig. 57: Vehicle Speed Signal Circuit between Radio Receiver and Combination Meter - Wiring Diagram
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

INSPECTION PROCEDURE

1. CHECK OPERATION OF SPEEDOMETER

a. Drive the vehicle and check if the function of the speedometer on the combination meter is normal.

OK: Actual vehicle speed and the speed indicated on the speedometer are the same.

HINT:



The speed indicated on the speedometer has an allowable margin of error. This can be tested
using a speedometer tester (calibrated chassis dynamometer). For details about testing and
the margin of error, refer to "OPERATION CHECK" in the meter/gauge system (see
OPERATION CHECK ).



The vehicle speed sensor is functioning normally when the indication on the speedometer is
normal.

NG: Go TO METER / GAUGE SYSTEM (See OPERATION CHECK )

OK: Go to Next Step

2009 Toyota Tundra

2009 ACCESSORIES AND EQUIPMENT Audio/Visual - Tundra

2. INSPECT RADIO RECEIVER

a. Disconnect the K3*1 or K9*2 receiver connector.

HINT:



*1: for Built-in Type Amplifier System



*2: for Separate Type Amplifier System

b. Measure the voltage.

1. Jack up the drive wheels.

2. Move the shift lever to the neutral position.

3. Turn the ignition switch to the ON position.

Fig. 58: Identifying K9 And K3 Connectors Terminals
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

2009 Toyota Tundra

2009 ACCESSORIES AND EQUIPMENT Audio/Visual - Tundra

4. Measure the voltage between terminal SPD of the wire harness connector and body ground

when the drive wheels are turned slowly.

OK: Voltage pulses as shown in the illustration.

Result:

RESULT REFERENCE

B: REPLACE RADIO RECEIVER (see REMOVAL )

C: REPLACE RADIO RECEIVER (see REMOVAL )

Fig. 59: Voltage Pattern
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

A: Go to Next Step

3. CHECK HARNESS AND CONNECTOR (COMBINATION METER - RADIO RECEIVER)

a. Disconnect the K3*1 or K9*2 receiver connector.

HINT:



*1: for Built-in Type Amplifier System



*2: for Separate Type Amplifier System

b. Disconnect the J28 meter connector.

c. Measure the resistance according to the value(s) in the table below.

Standard resistance:

for Separate Type Amplifier System

Result

Proceed to

NG

A

OK (for Column Shift Type)

B

OK (for Floor Shift Type)

C

2009 Toyota Tundra

2009 ACCESSORIES AND EQUIPMENT Audio/Visual - Tundra