DTC C1AB4: Open in Outer Mirror Indicator (Master) [12/2019 - 11/2023]: Procedure

1. Turn the ignition switch off.
2. Turn the ignition switch to ON.
3. Recheck for DTCs and check if the same DTC is output again.

   Body Electrical > Blind Spot Monitor Master > Trouble Codes 

   OK

   No DTCs are output.

   Result

   Result	Proceed to
   OK	A
   NG (w/ Seat Position Memory System)	B
   NG (w/o Seat Position Memory System)	C

Result: 

A 

USE SIMULATION METHOD TO CHECK. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [12/2019 - ] 

Result: 

C 

See step  6

Result: 

B 

See step  2

1. Disconnect the M43 blind spot monitor sensor LH (master) connector.
2. Disconnect the J23 outer mirror control ECU assembly LH connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   M43-4 (OMIL) - J23-13 (BDSL)	Always	Below 1 Ω
   J23-7 (GND) - Body ground	Always	Below 1 Ω

   Result

   Proceed to
   OK
   NG

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR 

Result: 

OK 

See step  3

1. Disconnect the J23 outer rear view mirror assembly LH connector.
2. Disconnect the z17 outer rear view mirror assembly LH connector.
3. Measure the resistance according to the value(s) in the table below.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   *a	Component without harness connected (Outer Mirror Control ECU Assembly LH)

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   J23-13 (BDSL) - z17-8 (BSL+)	Always	Below 1 Ω
   J23-7 (GND) - z17-12 (-)	Always	Below 1 Ω

   Result

   Proceed to
   OK
   NG

Result: 

NG 

REPLACE OUTER MIRROR CONTROL ECU ASSEMBLY LH. Refer to  REMOVAL [12/2019 - ] 

Result: 

OK 

See step  4

1. Remove the outer rear view mirror LH.

   Refer to REMOVAL [12/2019 - 11/2023]

2. Inspect the outer rear view mirror LH (outer rear view mirror indicator LH).

   Refer to INSPECTION [12/2019 - ]

   Result

   Proceed to
   OK
   NG

Result: 

OK 

REPLACE BLIND SPOT MONITOR SENSOR LH (MASTER). Refer to  REMOVAL [12/2019 - 10/2022]  , or refer to  REMOVAL [10/2022 - 11/2023] 

Result: 

NG 

See step  5

1. Remove the outer mirror LH.

   Refer to REMOVAL [12/2019 - ]

2. Inspect the outer mirror LH (outer rear view mirror indicator LH).

   Refer to INSPECTION [12/2019 - ]

   Result

   Proceed to
   OK
   NG

Result: 

OK 

REPLACE OUTER REAR VIEW MIRROR ASSEMBLY LH. Refer to  REMOVAL [12/2019 - 11/2023] 

Result: 

NG 

REPLACE OUTER MIRROR LH. Refer to  REMOVAL [12/2019 - ] 

1. Disconnect the M43 blind spot monitor sensor LH (master) connector.
2. Disconnect the J31 outer rear view mirror assembly LH connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   M43-4 (OMIL) - J31-3 (BSL+)	Always	Below 1 Ω

   Result

   Proceed to
   OK
   NG

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR 

Result: 

OK 

See step  7

1. Remove the outer rear view mirror LH.

   Refer to REMOVAL [12/2019 - 11/2023]

2. Inspect the outer rear view mirror LH (outer rear view mirror indicator LH).

   Refer to INSPECTION [12/2019 - ]

   Result

   Proceed to
   OK
   NG

Result: 

OK 

REPLACE BLIND SPOT MONITOR SENSOR LH (MASTER). Refer to  REMOVAL [12/2019 - 10/2022]  , or refer to  REMOVAL [10/2022 - 11/2023] 

Result: 

NG 

See step  8

1. Remove the outer mirror LH.

   Refer to REMOVAL [12/2019 - ]

2. Inspect the outer mirror LH (outer rear view mirror indicator LH).

   Refer to INSPECTION [12/2019 - ]

   Result

   Proceed to
   OK
   NG

Result: 

OK 

REPLACE OUTER REAR VIEW MIRROR ASSEMBLY LH. Refer to  REMOVAL [12/2019 - 11/2023] 

Result: 

NG 

REPLACE OUTER MIRROR LH. Refer to  REMOVAL [12/2019 - ]