Mute Signal Circuit Between Navigation Receiver Assembly and Stereo Component Amplifier

NAVIGATION SYSTEM: Mute Signal Circuit between Navigation Receiver Assembly and Stereo Component Amplifier

Mute Signal Circuit between Navigation Receiver Assembly and Stereo Component Amplifier

DESCRIPTION

This circuit sends a signal to the stereo component amplifier 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 is normal, no sound, or only an extremely small sound, can be produced.

WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

1. INSPECT STEREO COMPONENT AMPLIFIER





(a) Measure the voltage according to the value(s) in the table below.
Standard voltage:





OK -- PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE
NG -- Continue to next step.
2. CHECK HARNESS AND CONNECTOR (NAVIGATION RECEIVER ASSEMBLY - STEREO COMPONENT AMPLIFIER)





(a) Disconnect the navigation receiver assembly connector R7 and television display assembly connector S11.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.
3. REPLACE STEREO COMPONENT AMPLIFIER
(a) Replace the stereo component amplifier and check if it operates normally.
OK:
The navigation system operates normally.
OK -- NORMAL OPERATION
NG -- REPLACE NAVIGATION RECEIVER ASSEMBLY