Dtc B1208 Passenger Side Outer Mirror Ecu

Communication System. Lexus Is250, Is220D. Gse20 Ale20
Multiplex Communication. Lexus Is250, Is220D. Gse20 Ale20

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

INSPECT FUSE (FR DOOR RH (LHD), FR DOOR LH (RHD), MPX-B)

CHECK WIRE HARNESS (OUTER MIRROR CONTROL ECU - BATTERY AND BODY GROUND)

CHECK RESISTANCE OF COMMUNICATION LINE

DTC B1208 Passenger Side Outer Mirror ECU


DESCRIPTION

  1. This DTC is detected when communication between the outer mirror control ECU (passenger side outer mirror ECU) and gateway ECU stops for more than 10 seconds.

DTC No.
DTC Detection Condition
Trouble Area
B1208
Outer mirror control ECU (passenger side) communication stops
  1. Outer mirror control ECU (passenger side)
  2. Wire harness

WIRING DIAGRAM


Lexus Is250, Is220D. Gse20 Ale20.Multiplex Communication.Multiplex Communication System. Dtc B1208 Passenger Side Outer Mirror Ecu


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 B1208, repair the "+B or GND short malfunction of communication bus" DTCs first.
1.INSPECT FUSE (FR DOOR RH (LHD), FR DOOR LH (RHD), MPX-B)

  1. Remove the FR DOOR RH fuse from the main body ECU RH (cowl side J/B RH) (for LHD).

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

  1. Remove the MPX-B fuse from the engine room J/B No. 1.

  1. Measure the resistance of the fuse.

    Standard resistance:
    Below 1 Ω


NG
REPLACE FUSE
OK


2.CHECK WIRE HARNESS (OUTER MIRROR CONTROL ECU - BATTERY AND BODY GROUND)

  1. Disconnect the M10 ECU connector (for LHD).



    Lexus Is250, Is220D. Gse20 Ale20.Multiplex Communication.Multiplex Communication System. Dtc B1208 Passenger Side Outer Mirror Ecu

  1. Disconnect the L10 ECU connector (for RHD).

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

    Standard voltage:
    Tester Connection
    		Condition
    		Specified Condition
    *1BDR (M10-6) - Body ground
    *2BDR (L10-6) - Body ground
    		Always
    		10 to 14 V
    *1CPUB (M10-4) - Body ground
    *2CPUB (L10-4) - Body ground
    		Always
    		10 to 14 V
    Standard resistance:
    Tester Connection
    		Specified Condition
    *1GND (L10-1) - Body ground
    *2GND (M10-1) - Body ground
    		Below 1 Ω
    HINT:
    1. *1: LHD
    2. *2: RHD


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


3.CHECK RESISTANCE OF COMMUNICATION LINE

  1. Disconnect the M10 and J55 ECU connectors (for LHD).



  1. Disconnect the L10 and P33 ECU connector (for RHD).


    Lexus Is250, Is220D. Gse20 Ale20.Multiplex Communication.Multiplex Communication System. Dtc B1208 Passenger Side Outer Mirror Ecu

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

    Standard resistance:
    Tester Connection
    		Specified Condition
    *1MPX1 (M10-8) - MPX2 (J55-24)
    *2MPX1 (L10-8) - MPX1 (P33-27)
    		Below 1 Ω
    *1MPX1 (M10-8) - Body ground
    *2MPX1 (L10-8) - Body ground
    		10 kΩ or higher
    HINT:
    1. *1: LHD
    2. *2: RHD


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

REPLACE OUTER MIRROR CONTROL ECU (PASSENGER SIDE)