Main Body ECU Communication Stop Mode [11/2017 - ]: Procedure

1. Disconnect the cable from the negative (-) battery terminal.
2. Disconnect the O2 main body ECU (multiplex network body 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 Main Body ECU (Multiplex Network Body ECU))

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   O2-14 (CANH) - O2-13 (CANL)	Cable disconnected from negative (-) battery terminal	54 to 69 Ω

   Result

   Result
   OK
   NG

Result: 

NG 

REPAIR OR REPLACE CAN BRANCH LINES OR CONNECTOR (MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)) 

Result: 

OK 

See step  2

1. Remove the main body ECU (multiplex network body ECU).

   Refer to REMOVAL [09/2014 - ]

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

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   *1	Component without harness connected (Instrument Panel Junction Block Assembly)

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   MB-11 (GND1) - Body ground	Cable disconnected from negative (-) battery terminal	Below 1 Ω

   NOTE:

   Perform this inspection with the wire harness connected to the instrument panel junction block assembly.

3. Reconnect the cable to the negative (-) battery terminal.
4. Measure the voltage according to the value(s) in the table below.

   Standard Voltage

   Tester Connection	Condition	Specified Condition
   MB-31 (BECU) - Body ground	Always	11 to 14 V
   MB-30 (ACC) - Body ground	Engine switch on (ACC)	11 to 14 V
   MB-32 (IG) - Body ground	Engine switch on (IG)	11 to 14 V

   NOTE:

   Perform this inspection with the wire harness connected to the instrument panel junction block assembly.

   Result

   Result	Proceed to
   OK	A
   NG (BECU)	B
   NG (IG)	C
   NG (ACC)	D
   NG (GND1)	E

Result: 

A 

REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU). Refer to  REMOVAL [09/2014 - ] 

Result: 

C 

GO TO LIGHTING (INT) SYSTEM (IG SIGNAL CIRCUIT). Refer to  IG Signal Circuit [09/2014 - ] 

Result: 

D 

GO TO LIGHTING (INT) SYSTEM (ACC SIGNAL CIRCUIT). Refer to  ACC Signal Circuit [09/2014 - ] 

Result: 

E 

See step  4

Result: 

B 

See step  3

1. Disconnect the cable from the negative (-) battery terminal.
2. Disconnect the 4F instrument panel junction block assembly connector.
3. Reconnect the cable to the negative (-) battery terminal.
4. Measure the voltage according to the value(s) in the table below.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   *a	Front view of wire harness connector (to Instrument Panel Junction Block Assembly)

   Standard Voltage

   Tester Connection	Condition	Specified Condition
   4F-1 - Body ground	Always	11 to 14 V

   Result

   Result
   OK
   NG

Result: 

OK 

REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY. Refer to  REMOVAL [09/2014 - ] 

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT) 

1. Disconnect the cable from the negative (-) battery terminal.
2. Disconnect the 4B instrument panel junction block assembly 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 Instrument Panel Junction Block Assembly)

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   4B-7 - Body ground	Cable disconnected from negative (-) battery terminal	Below 1 Ω

   Result

   Result
   OK
   NG

Result: 

OK 

REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY. Refer to  REMOVAL [09/2014 - ] 

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR