Lexus IS250 IS220d GSE20 ALE20 - MULTIPLEX COMMUNICATION

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

INSPECT FUSE (FR DOOR LH)

CHECK WIRE HARNESS (POWER WINDOW MASTER SWITCH - BATTERY AND BODY GROUND)

CHECK RESISTANCE OF COMMUNICATION LINE

DTC B1206 P/W Master Switch Communication Stop

DESCRIPTION

This DTC is detected when communication between the multiplex network master switch (power window master switch) and gateway ECU stops for more than 10 seconds.
DTC No.DTC Detection ConditionTrouble Area
B1206Multiplex network master switch communication stops
Multiplex network master switch assembly (power window master switch)
Wire harness

WIRING DIAGRAM

Dtc B1206 P/W Master Switch Communication Stop. MULTIPLEX COMMUNICATION. Lexus IS250 IS220d GSE20 ALE20

INSPECTION PROCEDURE

  • HINT:
  • When "+B of GND short malfunction of communication bus" DTCs (B1214 and B1215) are detected at the same time as "communication stop" DTC B1206, repair the "+B or GND short malfunction of communication bus" DTCs first.
1.INSPECT FUSE (FR DOOR LH)

Remove the FR DOOR LH fuse from the main body ECU LH (cowl side J/B LH).

Measure the resistance of the fuse.

  • Standard resistance:
  • Below 1 Ω
NG
REPLACE FUSE
OK
2.CHECK WIRE HARNESS (POWER WINDOW MASTER SWITCH - BATTERY AND BODY GROUND)
Dtc B1206 P/W Master Switch Communication Stop. MULTIPLEX COMMUNICATION. Lexus IS250 IS220d GSE20 ALE20

Disconnect the M7 switch connector (for LHD).

Disconnect the L17 switch connector (for RHD).

Turn the engine switch on (IG).

Measure the voltage and resistance of the wire harness side connector.

  • Standard voltage:
  • Tester ConnectionConditionSpecified Condition
    *1BDR (M7-10) - Body ground
    *2BDR (L17-10) - Body ground    		Always10 to 14 V
  • HINT:
*1: LHD
*2: RHD
  • Standard resistance:
  • Tester ConnectionSpecified Connection
    *1GND (M7-2) - Body ground
    *2GND (L17-2) - Body ground    		Below 1 Ω
  • HINT:
*1: LHD
*2: RHD
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK
3.CHECK RESISTANCE OF COMMUNICATION LINE

Disconnect the M7, Q3 and P33 ECU connectors (for LHD).

Disconnect the L17, RJ and P33 ECU connector (for RHD).

Dtc B1206 P/W Master Switch Communication Stop. MULTIPLEX COMMUNICATION. Lexus IS250 IS220d GSE20 ALE20

Measure the resistance between the specified terminals on the wire harness side connectors.

  • Standard resistance:
  • Tester ConnectionSpecified Condition
    *1MPX1 (M7-7) - MPX1 (Q3-15)
    *2MPX1 (L17-7) - MPX1 (P33-27)    		Below 1 Ω
    *1MPX2 (M7-8) - MPX2 (P33-28)
    *2MPX2 (L17-8) - MPX1 (RJ-21)    		Below 1 Ω
  • HINT:
*1: LHD
*2: RHD
  • Result:
  • ResultProceed to
    Both are OKA
    One is OKB
    Both are NGC
B
REPAIR OR REPLACE HARNESS OR CONNECTOR AND REPLACE POWER WINDOW MASTER SWITCH
C
REPAIR OR REPLACE HARNESS OR CONNECTOR
A
REPLACE POWER WINDOW MASTER SWITCH
LEXUS IS250, IS220d / GSE20 ALE20
MULTIPLEX COMMUNICATION
Lexus IS250 IS220d GSE20 ALE20
MULTIPLEX COMMUNICATION SYSTEM