Precaution [12/2019 - 10/2022]

Refer to HOW TO PROCEED WITH TROUBLESHOOTING [12/2019 - 10/2022] 

1. Be careful when replacing parts. Incorrect replacement could affect the performance of the steering system and result in hazardous driving.

   Refer to PRECAUTION [12/2019 - 10/2022]

1. When disconnecting a wire harness from a CAN junction connector, use tape or tags to identify each connector and make sure to reconnect each connector to its original location on the CAN junction connector.

   HINT: 

   • There is a CAN junction that can be installed at the preferred installation position. When the connector is disconnected, connect it at its original location to prevent incorrect installation.
   • For identifying where to connect CAN junctions and CAN junction connectors, refer to "Terminals of ECU".

     Refer to TERMINALS OF ECU [12/2019 - 10/2022] 

1. When repairing a CAN line or other communication line, make sure the untwisted portion of the wires is as short as possible, and wrap the line with tape while twisting the Hi/Lo wires together so that there is no separation between them.
   NOTE:

   Untwisting and separation between wires may degrade equipment performance.

2. Do not use bypass wiring between connectors.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   *a	Bypass Wire

   NOTE:

   • The ability of the twisted bus lines to resist interference will be lost if bypass wiring is used.
   • Do not use a twisted pair of wires for bypass wiring.

1. When checking resistance with a tester, insert the tester probes from the backside (harness side) of the connector.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   *a	Tester Probe

2. When it is not possible to insert the tester from the backside of the connector, using service wires, measure from the front side of the connector.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   *a	Service Wire

1. When replacing a gateway equipped function ECU (sub bus monitoring ECU) with one which was installed to another vehicle, perform initialization of the sub bus monitoring ECU in order to clear stored bus information.

   Refer to UTILITY [12/2019 - 11/2023] 

   NOTE:

   If the stored bus information does not match the current sub bus configuration, DTCs may be stored and fail-safe functions may operate.

   HINT: 

   It is not necessary to perform initialization of a gateway monitoring ECU (sub bus monitoring ECU) when using a sub bus monitoring ECU which was installed to another vehicle with the same sub bus configuration.

1. Refer to precautions when replacing a gateway function equipped ECU (sub bus monitoring ECU) and initialize the connection information of the ECU.
2. Clear the DTCs and check that no DTCs are output.

1. Some optional navigation receivers/radio and display receivers are available as CAN compatible devices. Be aware that some optional navigation receivers/radio and display receivers do not have the same diagnostic features or characteristics of genuine navigation receivers/radio and display receivers.
   NOTE:

   • Optional navigation receivers/radio and display receivers receive data from the CAN communication system. However, most optional navigation receivers/radio and display receivers do not send signals to the CAN bus main line.
   • Most optional navigation receivers/radio and display receivers will not be displayed on the "CAN Bus Check" screen of the GTS.
   • When checking for DTCs using the GTS, DTCs for optional navigation receivers/radio and display receivers will not be displayed on the GTS.