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

1. Disconnect the I5 switch connector.
   Fig 1: Front View Of Wiring Harness Connector

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

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   I5-12 (E) - Body ground	Always	Below 1 Ω

   Standard Voltage

   Tester Connection	Condition	Specified Condition
   I5-11 (B) - Body ground	Always	11 to 14 V

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR, OR REPLACE FUSE 

OK: Go to next step 

1. Disconnect the E59 ECU connector.
   Fig 2: View Of E59 And I5 Wiring Harness Connectors

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

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   E59-10 (LIN2) - I5-17 (LIN1)	Always	Below 1 Ω
   I5-17 (LIN1) - Body ground	Always	10 kΩ or higher

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 → REPLACE MAIN BODY ECU (INSTRUMENT PANEL JUNCTION BLOCK) 

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