Navigation Multi Info Display. Navigation System (For Radio And Display Type) Mute Signal Circuit Between Radio Receiver And Stereo Component Amplifier

CHECK STEREO COMPONENT AMPLIFIER ASSEMBLY

CHECK HARNESS AND CONNECTOR (RADIO AND DISPLAY RECEIVER ASSEMBLY - STEREO COMPONENT AMPLIFIER ASSEMBLY)

CHECK STEREO COMPONENT AMPLIFIER ASSEMBLY (OUTPUT SIGNAL)

NAVIGATION SYSTEM (for Radio and Display Type) - Mute Signal Circuit between Radio Receiver and Stereo Component Amplifier

DESCRIPTION

This circuit sends a signal to the stereo component amplifier assembly to mute noise. Because of that, the noise produced by changing the sound source ceases.
If there is an open in the circuit, noise can be heard from the speakers when changing the sound source.
If there is a short in the circuit, even though the stereo component amplifier assembly is functioning normally, no sound or only an extremely faint sound can be heard.

WIRING DIAGRAM

Land Cruiser, Land Cruiser Prado. Grj150 Trj150,155 Kdj150,155 Lj150, Gdj150,155.Navigation Multi Info Display.Navigation System (For Radio And Display Type).Navigation System (For Radio And Display Type) Mute Signal Circuit Between Radio Receiver And Stereo Component Amplifier

INSPECTION PROCEDURE

1.CHECK STEREO COMPONENT AMPLIFIER ASSEMBLY

Measure the voltage according to the value(s) in the table below.
Standard Voltage:
Tester Connection
Switch Condition
Specified Condition
H63-1 (MUTE) - Body ground
Engine switch on (ACC), audio system playing
→ Changing modes
Above 3.5 V
→ Below 1 V
Text in Illustration
*a
Component with harness connected
(Stereo Component Amplifier Assembly)

Text in Illustration
*a	Component with harness connected (Stereo Component Amplifier Assembly)

Go to step 2

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE (LandCruiser RM000005MAG00FX.html)

2.CHECK HARNESS AND CONNECTOR (RADIO AND DISPLAY RECEIVER ASSEMBLY - STEREO COMPONENT AMPLIFIER ASSEMBLY)

Disconnect the H51 radio and display receiver assembly connector.

Disconnect the H63 stereo component amplifier assembly connector.

Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection
Condition
Specified Condition
H51-16 (MUT1) - H63-1 (MUTE)
Always
Below 1 Ω
H51-16 (MUT1) - Body ground
Always
10 kΩ or higher

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

3.CHECK STEREO COMPONENT AMPLIFIER ASSEMBLY (OUTPUT SIGNAL)

Disconnect the radio and display receiver assembly connector.

Measure the voltage according to the value(s) in the table below.
Standard Voltage:
Tester Connection
Switch Condition
Specified Condition
H51-16 (MUT1) - Body ground
Engine switch on (ACC), audio system is playing
Above 3.5 V
Text in Illustration
*a
Front view of wire harness connector
(to Radio and Display Receiver Assembly)

Text in Illustration
*a	Front view of wire harness connector (to Radio and Display Receiver Assembly)

REPLACE STEREO COMPONENT AMPLIFIER ASSEMBLY (LandCruiser RM000003AI9027X.html)

REPLACE RADIO AND DISPLAY RECEIVER ASSEMBLY (LandCruiser RM000003AHY02NX.html)

Tester Connection	Switch Condition	Specified Condition
H63-1 (MUTE) - Body ground	Engine switch on (ACC), audio system playing → Changing modes	Above 3.5 V → Below 1 V

Tester Connection	Condition	Specified Condition
H51-16 (MUT1) - H63-1 (MUTE)	Always	Below 1 Ω
H51-16 (MUT1) - Body ground	Always	10 kΩ or higher