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

1. Remove the instrument panel junction block assembly. Refer to REMOVAL .
   Fig 1: Inspecting Instrument Panel Junction Block Assembly

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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 communication 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
   2A-27 (LIN2) - MB-16 (LIN2)	Always	Below 1 Ω

   TEXT IN ILLUSTRATION
   
   

   *1	Component without harness connected (Instrument Panel Junction Block Assembly)
   *2	Component without harness connected (Instrument Panel Junction Block Assembly)

NG → See step   6 

OK: Go to next step 

1. Disconnect the I1 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
   2A-27 (LIN2) - I1-17 (LIN1)	Always	Below 1 Ω
   2A-27 (LIN2) - Body ground	Always	10 kΩ or higher

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK: Go to next step 

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

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   I1-12 (GND) - Body ground	Always	Below 1 Ω

   Standard Voltage

   Tester Connection	Condition	Specified Condition
   I1-11 (B) - I1-12 (GND)	Power switch off	11 to 14 V

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK: Go to next step 

1. Replace the multiplex network master switch assembly. Refer to REMOVAL .

NEXT: Go to next step 

1. Clear the DTC. Refer to DTC CHECK/CLEAR .
2. Recheck for DTCs.

   OK

   DTC B1206 is not output.

NG → See step   7 

OK → END (MULTIPLEX NETWORK MASTER SWITCH ASSEMBLY WAS DEFECTIVE)