Mute Signal Circuit between Stereo Component Amplifier and Telematics Transceiver: Procedure

INSPECT DCM (TELEMATICS TRANSCEIVER)

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

Fig 1: Identifying F38 DCM (Telematics Transceiver) Connector

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Standard Voltage

Tester Connection	Condition	Specified Condition
F38-17 (MUTE) - Body ground	Power switch on (ACC), audio system is playing → Emergency call mode	Above 3.5 V → Below 1 V

TEXT IN ILLUSTRATION

*1	Component with harness connected (DCM (Telematics Transceiver))

NG → See step 2

OK → See step 4

CHECK HARNESS AND CONNECTOR

Disconnect the stereo component amplifier assembly connector and DCM (telematics transceiver) connector.

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

Standard Resistance

Tester Connection	Condition	Specified Condition
F49-7 (TMUT) - F38-17 (MUTE)	Always	Below 1 Ω
F49-7 (TMUT) - Body ground	Always	10 kΩ or higher

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR

OK: Go to next step

INSPECT STEREO COMPONENT AMPLIFIER ASSEMBLY

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

Fig 2: Identifying F38 Stereo Component Amplifier Assembly Connector Terminals

Standard Voltage

Tester Connection	Condition	Specified Condition
F38-17 (MUTE) - Body ground	Power switch on (ACC)	Above 3.5 V

TEXT IN ILLUSTRATION

*1	Front view of wire harness connector (to DCM (Telematics Transceiver))

NG → See step 5

OK → See step 6

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE. Refer to PROBLEM SYMPTOMS TABLE
REPLACE STEREO COMPONENT AMPLIFIER ASSEMBLY. Refer to REMOVAL
REPLACE DCM (TELEMATICS TRANSCEIVER). Refer to REMOVAL