DTC U1331: Software Incompatibility with Body Control Module "B" [08/2017 - 08/2019]: Procedure

1. Check the main body ECU (multiplex network body ECU) part number.
   1. Check if the part number of the main body ECU (multiplex network body ECU) on the vehicle is correct.

      OK

      The parts number is correct.

Result: 

NG 

REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU). Refer to  REMOVAL [08/2017 - 08/2019] 

Result: 

OK 

See step  2

1. Clear the DTCs (Refer to DTC CHECK / CLEAR [08/2017 - 08/2019] ).
2. Recheck for DTCs and check if the same DTC is output again.
   RESULT
   
   

   Result	Proceed to
   No DTC is output	A
   DTC U1331 is output ("Blind Spot Monitor Master").	B
   DTC U1331 is output ("Blind Spot Monitor Slave").	C

Result: 

A 

USE SIMULATION METHOD TO CHECK 

(Refer to HOW TO PROCEED WITH TROUBLESHOOTING [08/2017 - 08/2018] , or refer to HOW TO PROCEED WITH TROUBLESHOOTING [08/2018 - 08/2019] )

Result: 

B 

REPLACE BLIND SPOT MONITOR SENSOR RH 

(Refer to PROCEDURE - Step 5 )

Result: 

C 

REPLACE BLIND SPOT MONITOR SENSOR LH 

(Refer to PROCEDURE - Step 4 )