Microphone Circuit between Microphone and Navigation Receiver Assembly: Procedure

1. Measure the voltage according to the value(s) in the table below.
   Fig 1: Identifying Navigation Receiver Assembly

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   Standard Voltage

   Tester Connection	Switch Condition	Specified Condition
   E25-17 (MACC) - Body ground	Ignition switch ACC	4 to 6 V

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

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   E25-18 (SGND) - Body ground	Always	Below 1 Ω
   E25-20 (MIN-) - Body ground	Always	Below 1 Ω

   TEXT IN ILLUSTRATION
   
   

   *a	Component with harness connected (Navigation Receiver Assembly)

NG → See step   6 

OK: Go to next step 

1. Disconnect the E25 navigation receiver assembly connector.
2. Disconnect the Q11 telephone microphone assembly connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   E25-5 (SNS2) - Q11-4 (SNS2)	Always	Below 1 Ω
   E25-17 (MACC) - Q11-1 (MACC)	Always	Below 1 Ω
   E25-19 (MIN+) - Q11-3 (MIC+)	Always	Below 1 Ω
   E25-20 (MIN-) - Q11-5 (MIC-)	Always	Below 1 Ω
   E25-5 (SNS2) - Body ground	Always	10 kΩ or higher
   E25-17 (MACC) - Body ground	Always	10 kΩ or higher
   E25-19 (MIN+) - Body ground	Always	10 kΩ or higher
   E25-20 (MIN-) - Body ground	Always	10 kΩ or higher
   E25-18 (SGND) - Body ground	Always	10 kΩ or higher

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK: Go to next step 

1. Measure the resistance according to the value(s) in the table below.
   Fig 2: Inspecting Telephone Microphone Assembly

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   Q11-4 (SNS2) - Q11-5 (MIC-)	Always	Below 1 Ω

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   *a	Component without harness connected (Telephone Microphone Assembly)

NG → See step   7 

OK: Go to next step 

1. Reconnect the E25 navigation receiver assembly connector.
2. Reconnect the Q11 telephone microphone assembly connector.
   Fig 3: Identifying Q11 Telephone Microphone Assembly Connector

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
3. Turn the ignition switch to ACC.
4. Connect an oscilloscope to terminals 3 (MIC+) and 5 (MIC-) of the Q11 telephone microphone assembly connector.
5. Check the waveform of the telephone microphone assembly using the oscilloscope.

   Result

   Result	Proceed to
   A waveform synchronized with the voice input to the telephone microphone assembly is output	A
   A waveform synchronized with the voice input to the telephone microphone assembly is not output	B

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   *a	Component with harness connected (Telephone Microphone Assembly)

B → See step   8 

A → See step   5