Main Body ECU Communication Stop Mode: Procedure

1. Disconnect the cable from the negative (-) battery terminal before measuring the resistance of the CAN main wire or CAN 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 .

NEXT: Go to next step 

1. Disconnect the D9 main body ECU (instrument panel junction block assembly) connector.
   Fig 1: Disconnecting D9 Main Body 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
   D9-5 (CANH) - D9-6 (CANL)	Ignition switch off	54 to 69 Ω

   TEXT IN ILLUSTRATION
   
   

   *a	Rear view of wire harness connector (to Main Body ECU [Instrument Panel Junction Block Assembly])

NG → REPAIR OR REPLACE MAIN BODY ECU CAN BRANCH WIRE OR CONNECTOR (CANH, CANL) 

OK: Go to next step 

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 .

   Fig 2: Disconnecting Disconnect The 1A, 1D, 1F 1M And D9 Main Body ECU (Instrument Panel Junction Block Assembly) Connectors

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   TEXT IN ILLUSTRATION
   
   

   *a

   Front view of wire harness connector (to Main Body ECU [Instrument Panel Junction Block Assembly])

   -

   -

2. Disconnect the 1A, 1D, 1F and 1M main body ECU (instrument panel junction block assembly) connectors.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   1F-10 (GND1) - Body ground	Always	Below 1 Ω
   1M-9 (GND2) - Body ground	Always	Below 1 Ω
   D9-1 (GND3) - Body ground	Always	Below 1 Ω

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

   Standard Voltage

   Tester Connection	Condition	Specified Condition
   1D-16 (ALTB) - Body ground	Always	11 to 14 V
   1A-1 (ACC) - Body ground	Always	11 to 14 V
   1A-1 (IG) - Body ground	Always	11 to 14 V

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK → REPLACE MAIN BODY ECU (INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY)