DTC C1A75: Lost Communication with Steering Vibrator System [10/2016 - 09/2020]: Procedure

1. Turn the engine switch off.
2. Disconnect the S18 forward recognition camera connector.
3. Disconnect the z15 spiral cable sub-assembly connector.
4. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   z15-2 (LDA) (spiral cable sub-assembly side) - S18-2 (STRV)	Always	Below 1 Ω
   z15-2 (LDA) (spiral cable sub-assembly side) or S18-2 (STRV) - Body ground	Engine switch off	10 kΩ or higher

5. Connect the S18 forward recognition camera connector.
6. Connect the z15 spiral cable sub-assembly connector.

   Result

   Proceed to
   OK
   NG

Result: 

NG 

See step  9

Result: 

OK 

See step  2

1. Disconnect the z18 spiral cable sub-assembly connector.
2. Turn the engine switch on (IG).
3. Measure the voltage according to the value(s) in the table below.

   Standard Voltage

   Tester Connection	Condition	Specified Condition
   z18-4 (BHT) (spiral cable sub-assembly side) - Body ground	Engine switch on (IG)	11 to 14 V

4. Turn the engine switch off.
5. Connect the z18 spiral cable sub-assembly connector.

   Result

   Proceed to
   OK
   NG

Result: 

NG 

See step  8

Result: 

OK 

See step  3

1. Disconnect the z18 spiral cable sub-assembly connector.
2. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   z18-1 (EHT) (spiral cable sub-assembly side) - Body ground	Always	Below 1 Ω

3. Connect the z18 spiral cable sub-assembly connector.

   Result

   Proceed to
   OK
   NG

Result: 

NG 

See step  7

Result: 

OK 

See step  4

1. Disconnect the z15 No. 1 switch wire connector from the spiral cable sub-assembly.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   *a	No. 1 Switch Wire Connector (to Spiral Cable Sub-assembly)
   *b	No. 1 Switch Wire Connector (to Steering Vibration ECU)

2. Disconnect the A No. 1 switch wire connector from the steering vibration ECU.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   z15-2 (LDA) - A-2 (LDA)	Always	Below 1 Ω
   z15-2 (LDA) or A-2 (LDA) - Body ground	Always	1 kΩ or higher

4. Connect the A No. 1 switch wire connector to the steering vibration ECU.
5. Connect the z15 No. 1 switch wire connector to the spiral cable sub-assembly.

   Result

   Proceed to
   OK
   NG

Result: 

NG 

REPLACE NO. 1 SWITCH WIRE 

for A760H: Refer to COMPONENTS [10/2016 - ]

for AA81E: Refer to COMPONENTS [10/2016 - ]

Result: 

OK 

See step  5

1. Replace the steering vibration ECU.

   Refer to REMOVAL [10/2016 - 11/2021]

   Result

   Proceed to
   NEXT

Result: 

NEXT 

See step  6

1. Clear the DTCs.

   Refer to DTC CHECK / CLEAR [10/2016 - 09/2020]

   Chassis > LKA/LDA > Clear DTCs 

2. Perform the following procedure.

   HINT: 

   If the following procedure is not performed, the previously output DTC cannot be detected.

   1. Turn the engine switch on (IG).
   2. Turn the lane departure alert system ON.
   3. Drive the vehicle at a speed of 5 km/h (4 mph) or more for 5 minutes or more.
3. Check for DTCs.

   Refer to DTC CHECK / CLEAR [10/2016 - 09/2020]

   Chassis > LKA/LDA > Trouble Codes 

   Result

   Result	Proceed to
   DTC C1A75 is not output	A
   DTC C1A75 is output	B

Result: 

A 

END (STEERING VIBRATION ECU WAS DEFECTIVE) 

Result: 

B 

REPLACE FORWARD RECOGNITION CAMERA. Refer to  COMPONENTS [10/2016 - 09/2020] 

1. Disconnect the K140 spiral cable sub-assembly connector.
2. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   K140-2 (EHT) (connector side) - Body ground	Always	Below 1 Ω

3. Connect the K140 spiral cable sub-assembly connector.

   Result

   Proceed to
   OK
   NG

Result: 

OK 

REPLACE SPIRAL CABLE SUB-ASSEMBLY. Refer to  COMPONENTS [10/2016 - ] 

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR (SPIRAL CABLE SUB-ASSEMBLY - BODY GROUND) 

1. Disconnect the K140 spiral cable sub-assembly connector.
2. Turn the engine switch on (IG).
3. Measure the voltage according to the value(s) in the table below.

   Standard Voltage

   Tester Connection	Condition	Specified Condition
   K140-4 (BHT) (connector side) - Body ground	Engine switch on (IG)	11 to 14 V

4. Turn the engine switch off.
5. Connect the K140 spiral cable sub-assembly connector.

   Result

   Proceed to
   OK
   NG

Result: 

OK 

REPLACE SPIRAL CABLE SUB-ASSEMBLY. Refer to  COMPONENTS [10/2016 - ] 

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR (STEERING VIBRATION ECU POWER SOURCE CIRCUIT) 

1. Disconnect the S18 forward recognition camera connector.
2. Disconnect the K26 spiral cable sub-assembly connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   K26-9 (LDA) - S18-2 (STRV)	Always	Below 1 Ω
   K26-9 (LDA) or S18-2 (STRV) - Body ground	Engine switch off	10 kΩ or higher

4. Connect the K26 spiral cable sub-assembly connector.
5. Connect the S18 forward recognition camera connector.

   Result

   Proceed to
   OK
   NG

Result: 

OK 

REPLACE SPIRAL CABLE SUB-ASSEMBLY. Refer to  COMPONENTS [10/2016 - ] 

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR