Main Body ECU Communication Stop Mode: Procedure

1. Turn the ignition switch off.
   Fig 1: Checking Main Body ECU E63 Connector Terminals

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   TEXT IN ILLUSTRATION
   
   

   *a	Front view of wire harness connector: (to Main Body ECU)

2. Disconnect the main body ECU connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Switch Condition	Specified Condition
   E63-23 (CANH) - E63-22 (CANL)	Ignition switch off	54 to 69 Ω

NG → REPAIR OR REPLACE CAN BUS BRANCH WIRE OR CONNECTOR (MAIN BODY ECU BRANCH WIRE) 

OK: Go to next step 

1. Disconnect the driver side junction block connectors.
   Fig 2: Checking Main Body ECU 2E & 2B Connector Terminals

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   TEXT IN ILLUSTRATION
   
   

   *a	Front view of wire harness connector: (to Driver Side Junction Block)

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

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   2E-17 (GND1) - Body ground	Always	Below 1 Ω

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

   Standard Voltage

   Tester Connection	Condition	Specified Condition
   2B-30 (BECU) - Body ground	Always	10 to 14 V

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

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