Microphone Circuit between Microphone and Navigation Receiver Assembly [08/2015 - 08/2017]: Procedure

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

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   Standard Resistance

   Tester Connection	Condition	Specified Condition
   I53-19 (MIN-) - Body ground	Always	Below 1 Ω

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

   Standard Voltage

   Tester Connection	Switch Condition	Specified Condition
   I53-4 (MACC) - Body ground	Ignition switch ACC	4.75 to 5.25 V

   TEXT IN ILLUSTRATION
   
   

   *a	Component with harness connected (Navigation Receiver Assembly)

Result: 

NG 

REPLACE NAVIGATION RECEIVER ASSEMBLY 

(Refer to REMOVAL [08/2015 - 08/2019] )

Result: 

OK 

See step  2

1. Disconnect the I53 navigation receiver assembly connector.
2. Disconnect the U7 roof console box assembly connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   I53-4 (MACC) - U7-10 (ACC)	Always	Below 1 Ω
   I53-5 (MIN+) - U7-9 (MIC+)	Always	Below 1 Ω
   I53-19 (MIN-) - U7-8 (MIC-)	Always	Below 1 Ω
   I53-6 (SNS2) - U7-14 (SGND)	Always	Below 1 Ω
   I53-4 (MACC) - Body ground	Always	10 kΩ or higher
   I53-5 (MIN+) - Body ground	Always	10 kΩ or higher
   I53-19 (MIN-) - Body ground	Always	10 kΩ or higher
   I53-18 (SGND) - Body ground	Always	10 kΩ or higher
   I53-6 (SNS2) - Body ground	Always	10 kΩ or higher

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR 

Result: 

OK 

See step  3

1. Replace the telephone microphone assembly with a known good one (Refer to REMOVAL [08/2015 - 08/2017] ).
2. Check if the same problem occurs again.

   OK

   Malfunction disappears.

   RESULT
   
   

   Result	Proceed to
   OK	A
   NG (for Short Type Overhead Console Box)	B
   NG (for Long Type Overhead Console Box)	C

Result: 

A 

END (TELEPHONE MICROPHONE ASSEMBLY IS DEFECTIVE) 

Result: 

B 

REPLACE ROOF CONSOLE BOX ASSEMBLY 

(Refer to REMOVAL [08/2015 - 08/2019] )

Result: 

C 

REPLACE ROOF CONSOLE BOX ASSEMBLY 

(Refer to REMOVAL [08/2015 - 08/2017] )