DTC C1A4A: Skid Control Buzzer Circuit [09/2015 - 08/2019]: Procedure

1. Clear the DTCs.

   Refer to DTC CHECK / CLEAR [09/2015 - 08/2019]

   Body Electrical > Pre-Collision 2 > Clear DTCs 

2. Perform the Active Test according to the display on the Techstream.
   NOTE:

   Perform the Active Test for 1 second or more.

   HINT: 

   Performing the Active Test for 1 second or more causes DTC C1A4A to be stored if the DTC detection conditions are met.

   Body Electrical > Pre-Collision 2 > Active Test 

   Tester Display	Measurement Item	Control Range	Diagnostic Note
   PCS Crash Alarm Buzzer	Skid control buzzer assembly	ON / OFF	Test possible with engine switch on (IG), vehicle stopped

   Body Electrical > Pre-Collision 2 > Active Test 

   Tester Display
   PCS Crash Alarm Buzzer

3. Check for DTCs.

   Refer to DTC CHECK / CLEAR [09/2015 - 08/2019]

   Body Electrical > Pre-Collision 2 > Trouble Codes 

   Result

   Result	Proceed to
   DTC C1A4A is not output	A
   DTC C1A4A is output	B

Result: 

A 

USE SIMULATION METHOD TO CHECK. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [09/2015 - 08/2016]  , or refer to  HOW TO PROCEED WITH TROUBLESHOOTING [08/2016 - 12/2017]  , or refer to  HOW TO PROCEED WITH TROUBLESHOOTING [12/2017 - 08/2019] 

Result: 

B 

See step  2

1. Disconnect the A15 skid control buzzer assembly connector.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   *a	Front view of wire harness connector (to Skid Control Buzzer Assembly)

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

   Standard Voltage

   Tester Connection	Condition	Specified Condition
   A15-2 (IG1) - Body ground	Engine switch on (IG)	11 to 14 V
   	Engine switch off	Below 1 V

3. Connect the A15 skid control buzzer assembly connector.

   Result

   Proceed to
   OK
   NG

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR (SKID CONTROL BUZZER ASSEMBLY - BATTERY) 

Result: 

OK 

See step  3

1. Disconnect the A15 skid control buzzer assembly connector.
2. Disconnect the A72 driving support ECU assembly connector.
3. Measure the resistance according to the value (s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   A15-1 (BZ) - A72-3 (BZ)	Always	Below 1 Ω
   A15-1 (BZ) or A72-3 (BZ) - Body ground	Always	10 kΩ or higher

4. Connect the A72 driving support ECU assembly connector.
5. Connect the A15 skid control buzzer assembly connector.

   Result

   Proceed to
   OK
   NG

Result: 

OK 

See step  6

Result: 

NG 

See step  4

1. Repair or replace the harness or connector.

   Result

   Proceed to
   NEXT

Result: 

NEXT 

See step  5

1. Clear the DTCs.

   Refer to DTC CHECK / CLEAR [09/2015 - 08/2019]

   Body Electrical > Pre-Collision 2 > Clear DTCs 

2. Perform the Active Test according to the display on the Techstream.
   NOTE:

   Perform the Active Test for 1 second or more.

   HINT: 

   Performing the Active Test for 1 second or more causes DTC C1A4A to be stored if the DTC detection conditions are met.

   Body Electrical > Pre-Collision 2 > Active Test 

   Tester Display	Measurement Item	Control Range	Diagnostic Note
   PCS Crash Alarm Buzzer	Skid control buzzer assembly	ON / OFF	Test possible with engine switch on (IG), vehicle stopped

   Body Electrical > Pre-Collision 2 > Active Test 

   Tester Display
   PCS Crash Alarm Buzzer

3. Check for DTCs.

   Refer to DTC CHECK / CLEAR [09/2015 - 08/2019]

   Body Electrical > Pre-Collision 2 > Trouble Codes 

   Result

   Result	Proceed to
   DTC C1A4A is not output	A
   DTC C1A4A is output	B

Result: 

A 

END 

Result: 

B 

See step  6

1. Turn the engine switch on (IG).
2. Check if the skid control buzzer assembly is sounding.

   Result

   Result	Proceed to
   The skid control buzzer assembly does not sound when the engine switch is on (IG)	A
   The skid control buzzer assembly sounds continuously when the engine switch is on (IG)	B

Result: 

B 

See step  8

Result: 

A 

See step  7

1. Remove the skid control buzzer assembly.

   Refer to REMOVAL [09/2015 - 08/2016] , or refer to REMOVAL [08/2016 - 08/2019]

2. Inspect the skid control buzzer assembly.

   Refer to INSPECTION [09/2015 - ]

   Result

   Result	Proceed to
   Skid control buzzer assembly is abnormal	A
   Skid control buzzer assembly is normal	B

Result: 

B 

See step  9

Result: 

A 

See step  8

1. Replace the skid control buzzer assembly.

   Refer to REMOVAL [09/2015 - 08/2016] , or refer to REMOVAL [08/2016 - 08/2019]

   Result

   Proceed to
   NEXT

Result: 

NEXT 

See step  9

1. Clear the DTCs.

   Refer to DTC CHECK / CLEAR [09/2015 - 08/2019]

   Body Electrical > Pre-Collision 2 > Clear DTCs 

2. Perform the Active Test according to the display on the Techstream.
   NOTE:

   Perform the Active Test for 1 second or more.

   HINT: 

   Performing the Active Test for 1 second or more causes DTC C1A4A to be stored if the DTC detection conditions are met.

   Body Electrical > Pre-Collision 2 > Active Test 

   Tester Display	Measurement Item	Control Range	Diagnostic Note
   PCS Crash Alarm Buzzer	Skid control buzzer assembly	ON / OFF	Test possible with engine switch on (IG), vehicle stopped

   Body Electrical > Pre-Collision 2 > Active Test 

   Tester Display
   PCS Crash Alarm Buzzer

3. Check for DTCs.

   Refer to DTC CHECK / CLEAR [09/2015 - 08/2019]

   Body Electrical > Pre-Collision 2 > Trouble Codes 

   Result

   Result	Proceed to
   DTC C1A4A is not output	A
   DTC C1A4A is output	B

Result: 

A 

END 

Result: 

B 

REPLACE DRIVING SUPPORT ECU ASSEMBLY. Refer to  COMPONENTS [09/2015 - 08/2019]