Mute Signal Circuit between Radio Receiver and Stereo Component Amplifier: Procedure

1. Measure the voltage according to the value(s) in the table below.
   Fig 1: F69 Stereo Component Amplifier Assembly Connector Terminal

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   Standard Voltage

   Tester Connection	Condition	Specified Condition
   F69-1 (MUTE) - Body ground	Power switch on (ACC), audio system is playing → Changing sources	Above 2.5 V → Below 0.5 V

   TEXT IN ILLUSTRATION
   
   

   *1	Component with harness connected (Stereo Component Amplifier Assembly)

NG → See step   2 

OK → See step   4 

1. Disconnect the radio receiver assembly and stereo component amplifier assembly connectors.
2. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   F66-7 (MUTE) - F69-1 (MUTE)	Always	Below 1 Ω
   F66-7 (MUTE) - Body ground	Always	10 kΩ or higher

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK: Go to next step 

1. Reconnect the stereo component amplifier assembly connector.
   Fig 2: Identifying F66 Stereo Component Amplifier Assembly Connector

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Measure the voltage according to the value(s) in the table below.

   Standard Voltage

   Tester Connection	Condition	Specified Condition
   F66-7 (MUTE) - Body ground	Power switch on (ACC), audio system is playing	Above 2.5 V

   TEXT IN ILLUSTRATION
   
   

   *1	Front view of wire harness connector (to Radio Receiver Assembly)

NG → See step   6 

OK → See step   5