Bus Buffer ECU Communication Stop Mode [09/2022 - ]: Procedure

1. Check whether dealer installed options that support CAN communication are installed.

   Result

   Result	Proceed to
   Installed	A
   Not installed	B

Result: 

B 

See step  3

Result: 

A 

See step  2

1. Disconnect the cable from the negative (-) auxiliary battery terminal.
2. Disconnect the I174 option connector (bus buffer ECU) connector.
3. Measure the resistance according to the value(s) in the table below.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   *a	Front view of wire harness connector (to Option Connector (Bus Buffer ECU))

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   I174-2 (CAN+) - I174-1 (CAN-)	Cable disconnected from negative (-) auxiliary battery terminal	108 to 132 Ω

   Result

   Result
   OK
   NG

Result: 

OK 

REPAIR OR REPLACE CAN COMPATIBLE OPTIONAL DEVICE 

Result: 

NG 

REPAIR OR REPLACE CAN MAIN BUS LINES OR CONNECTOR (OPTION CONNECTOR (BUS BUFFER ECU)) 

1. Initialize the ECU.

   Body Electrical > Central Gateway > Utility 

   Tester Display
   Initialization

   Body Electrical > Main Body > Utility 

   Tester Display
   Initialization

2. Clear the DTCs.

   Body Electrical > Main Body > Clear DTCs 

3. Read the DTCs.

   Body Electrical > Main Body > Trouble Codes 

   Result

   Result	Proceed to
   DTC U1117-87 is not output from main body ECU (multiplex network body ECU)	A
   DTC U1117-87 is output from main body ECU (multiplex network body ECU)	B

Result: 

A 

END 

Result: 

B 

REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) 

Refer to REMOVAL [09/2022 - 11/2022] , or refer to REMOVAL [11/2022 - 09/2024] , or refer to REMOVAL [09/2024 - ]