Bus Buffer ECU Communication Stop Mode [09/2022 - 11/2022]: Procedure

WARNING: This page is about a different car, the 2023 Toyota GR Corolla and 2023 Toyota Corolla. However, it is still accessible from the selected car via links, so may be relevant.

CHECK VEHICLE TYPE

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

Result

Result	Proceed to
Installed	A
Not installed	B

Result:

See step 3

Result:

See step 2

CHECK FOR OPEN IN CAN BUS LINES (OPTION CONNECTOR (BUS BUFFER ECU) MAIN LINE)

Disconnect the cable from the negative (-) battery terminal.
Disconnect the I174 option connector (bus buffer ECU) connector.

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 (-) battery terminal	108 to 132 Ω

Result

Result
OK
NG

Result:

REPAIR OR REPLACE CAN COMPATIBLE OPTIONAL DEVICE

Result:

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

CHECK FOR DTC

Initialize the ECU.

Body Electrical > Central Gateway > Utility

Tester Display
Initialization

Body Electrical > Main Body > Utility

Tester Display
Initialization

Clear the DTCs.
Body Electrical > Main Body > Clear DTCs

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:

END

Result:

REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)

Refer to REMOVAL [09/2022 - 11/2022]