DTC B1206: P/W Master Switch Communication Stop: Procedure

1. Remove the instrument panel junction block assembly. Refer to REMOVAL [06/2012 - ] .
   Fig 1: Identifying Instrument Panel Junction Block Assembly Connector Terminals

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2. Remove the main body ECU (multiplex network body ECU) from the instrument panel junction block assembly.
3. Measure the resistance according to the value(s) in the table below.

   HINT: 

   This inspection is to check the LIN line in the instrument panel junction block assembly that connects the wire harness to the built-in main body ECU (multiplex network body ECU).

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   3B-30 (LIN2) - MB-16 (LIN2)	Always	Below 1 Ω

   TEXT IN ILLUSTRATION
   
   

   *a

   Component without harness connected (Instrument Panel Junction Block Assembly)

   *b

   Component without harness connected (Instrument Panel Junction Block Assembly)

NG → See step   6 

OK: Go to next step 

1. Disconnect the M4 multiplex network master switch assembly connector.
2. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   3B-30 (LIN2) - M4-17 (LIN1)	Always	Below 1 Ω
   3B-30 (LIN2) - Body ground	Always	10 kΩ or higher

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK: Go to next step 

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

   Standard Voltage

   Tester Connection	Condition	Specified Condition
   M4-11 (B) - M4-12 (GND)	Always	11 to 14 V

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

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   M4-12 (GND) - Body ground	Always	Below 1 Ω

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK: Go to next step 

1. Replace the multiplex network master switch assembly. Refer to REMOVAL [06/2012 - ] .

NEXT: Go to next step 

1. Clear the DTCs. Refer to DTC CHECK / CLEAR [06/2012 - ] .
2. Recheck for DTCs.

   OK

   DTC B1206 is not output.

NG → See step   7 

OK → END (MULTIPLEX NETWORK MASTER SWITCH WAS DEFECTIVE)