DTC U1100: Lost Communication with Seat Belt Control ECU [12/2015 - 11/2017]: Procedure

Result: 

NEXT 

See step  2

1. Disconnect the cable from the negative (-) battery terminal before measuring the resistances of the main wire and the branch wire.
   WARNING:

   Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.

   NOTE:

   When disconnecting the cable, some systems need to be initialized after the cable is reconnected (Refer to INITIALIZATION [12/2015 - 08/2016] , or refer to INITIALIZATION [08/2016 - 11/2017] )

Result: 

NEXT 

See step  3

1. Disconnect the seat belt control ECU connector.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

   Standard Resistance

   Tester Connection	Switch Condition	Specified Condition
   D83-1 (CANH) - D83-2 (CANL)	ignition switch off	54 to 69 Ω

   TEXT IN ILLUSTRATION
   
   

   *a	Front view of wire harness connector (to Seat Belt Control ECU)

Result: 

NG 

REPAIR OR REPLACE SEAT BELT CONTROL ECU BRANCH WIRE OR CONNECTOR (CAN-H, CAN-L) 

Result: 

OK 

See step  4

1. Connect the cable to the negative (-) battery terminal.
   NOTE:

   When disconnecting the cable, some systems need to be initialized after the cable is reconnected (Refer to INITIALIZATION [12/2015 - 08/2016] , or refer to INITIALIZATION [08/2016 - 11/2017] )

2. Disconnect the seat belt control ECU connectors.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   D84-8 (PGND) - Body ground	Always	Below 1 Ω

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

   Standard Voltage

   Tester Connection	Switch Condition	Specified Condition
   D84-7 (+B) - Body ground	Always	11 to 14 V
   D83-8 (IG1) - Body ground	Ignition switch ON	11 to 14 V

   TEXT IN ILLUSTRATION
   
   

   *a	Front view of wire harness connector (to Seat Belt Control ECU)

Result: 

OK 

REPLACE SEAT BELT CONTROL ECU 

(Refer to REMOVAL [12/2015 - 11/2017] )

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR