DTC U0233: Lost Communication with Blind Spot Monitor Master Module [10/2014 - 09/2017]: Procedure

1. Check for DTCs.

   Body Electrical > Gateway > Trouble Codes 

   HINT: 

   If DTC U1002 is output from the gateway of the network gateway ECU, this indicates a sub bus 2 malfunction. Troubleshoot for DTC U1002 and check for malfunctions in sub bus 2.

   Result

   Result	Proceed to
   U1002 is not output from network gateway ECU	A
   U1002 is output from network gateway ECU	B

Result: 

B 

GO TO DIAGNOSIS PROCEDURE INDICATED BY OUTPUT DTC. Refer to  DTC U1002: Lost Communication with Gateway Module [10/2014 - 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 Blind Spot Monitor Sensor LH)

2. Disconnect the blind spot monitor sensor LH connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   V1-2 (CA1P) - V1-7 (CA1N)	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 (BLIND SPOT MONITOR SENSOR LH) 

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 Blind Spot Monitor Sensor LH)

   NOTE:

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

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

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

   Standard Voltage

   Tester Connection	Switch Condition	Specified Condition
   V1-5 (BLB) - Body ground	Engine switch on (IG)	11 to 14 V

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

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   V1-10 (BLGD) - Body ground	Always	Below 1 Ω

   Result

   Proceed to
   OK
   NG

Result: 

OK 

REPLACE BLIND SPOT MONITOR SENSOR LH. Refer to  REMOVAL [10/2014 - 09/2017] 

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR