DTC U0230: Lost Communication with Rear Gate Module [09/2016 - 09/2017]: Procedure

1. Check for DTCs.

   Body Electrical > Main Body > Trouble Codes 

   HINT: 

   If DTC U1002 is output from the gateway of the main body ECU (multiplex network body ECU), this indicates a sub bus 1 malfunction. Troubleshoot for DTC U1002 and check for malfunctions in sub bus 1.

   Result

   Result	Proceed to
   DTC U1002 is not output from main body ECU (multiplex network body ECU)	A
   DTC U1002 is output from main body ECU (multiplex network body ECU)	B

Result: 

B 

GO TO DIAGNOSIS PROCEDURE INDICATED BY OUTPUT DTC. Refer to  DTC U1002: Lost Communication with Gateway Module (Main Body) [09/2016 - 09/2017]  

Result: 

A 

See step  2

1. Disconnect the cable from the negative (-) battery terminal.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   *a	Front view of wire harness connector (to Multiplex Network Door ECU)

2. Disconnect the multiplex network door ECU connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   Y26-39 (CANP) - Y26-40 (CANN)	Cable disconnected from negative (-) battery terminal	54 to 69 Ω

   Result

   Proceed to
   OK
   NG

Result: 

NG 

REPAIR OR REPLACE CAN BRANCH WIRE OR CONNECTOR (MULTIPLEX NETWORK DOOR ECU) 

Result: 

OK 

See step  3

1. Reconnect the cable to the negative (-) battery terminal.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   *a	Front view of wire harness connector (to Multiplex Network Door ECU)

   NOTE:

   When disconnecting the cable, some systems need to be initialized after the cable is reconnected.

   Refer to INITIALIZATION [10/2014 - 09/2017]

2. Disconnect the multiplex network door ECU connector.
3. Measure the voltage according to the value(s) in the table below.

   Standard Voltage

   Tester Connection	Condition	Specified Condition
   Y26-20 (ECUB) - Body ground	Always	11 to 14 V
   Y27-1 (B) - Body ground	Always	11 to 14 V
   Y26-18 (IG) - Body ground	Engine switch on (IG)	11 to 14 V

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

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   Y27-10 (GND) - Body ground	Always	Below 1 Ω

   Result

   Proceed to
   OK
   NG

Result: 

OK 

REPLACE MULTIPLEX NETWORK DOOR ECU. Refer to  REMOVAL [09/2016 - ] 

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR