DESCRIPTION
Based on dynamic radar cruise control system operation, the forward recognition camera provides warnings to the driver by sounding the skid control buzzer.
DTC C1A4A is stored when a malfunction is detected in the skid control buzzer circuit.
DTC No. |
Detection Item |
DTC Detection Condition |
Trouble Area |
---|---|---|---|
C1A4A |
Skid Control Buzzer Circuit |
While the vehicle speed is 36 km/h (22 mph) or more and the dynamic radar cruise control system is operating, the forward recognition camera detects a malfunction in the skid control buzzer circuit for approximately 0.4 seconds or more. |
|
WIRING DIAGRAM
CAUTION / NOTICE / HINT
NOTICE:
Click here
Click here
PROCEDURE
1. |
CHECK FOR DTCs (PRE-COLLISION SYSTEM) |
(a) Check for DTCs of the pre-collision system.
Click here
HINT:
The dynamic radar cruise control system only stores DTC C1A4A when the vehicle speed reaches 36 km/h (22 mph), however the pre-collision system stores this DTC at any vehicle speed. If DTC C1A4A is stored by the pre-collision system, perform troubleshooting of the pre-collision system first.
Result |
Proceed to |
---|---|
DTC C1A4A is not output |
A |
DTC C1A4A is output |
B |
B |
GO TO PRE-COLLISION SYSTEM |
|
2. |
CHECK FOR DTCs (RADAR CRUISE 2) |
(a) Clear the DTCs.
Click here
(b) Make sure that the DTC detection conditions are met.
HINT:
If the detection conditions are not met, the system cannot detect the malfunction.
(c) Perform the Active Test according to the display on the Techstream.
Click here
NOTICE:
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.
Powertrain > Radar Cruise2 > Active Test
Tester Display |
Measurement Item |
Control Range |
Diagnostic Note |
---|---|---|---|
Radar Cruise Stop Buzzer |
Skid control buzzer (stop sound) |
ON or OFF |
Buzzer can be heard |
Radar Cruise Approach Alarm Buzzer |
Skid control buzzer (approach sound) |
ON or OFF |
Buzzer can be heard |
(d) Check for DTCs.
Click here
Result |
Proceed to |
---|---|
DTC C1A4A is not output |
A |
DTC C1A4A is output |
B |
A |
USE SIMULATION METHOD TO CHECK |
|
3. |
INSPECT TERMINAL VOLTAGE |
(a) Disconnect the skid control buzzer connector. |
|
(b) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
Tester Connection |
Condition |
Specified Condition |
---|---|---|
N38-2 (IG1) - Body ground |
Ignition switch ON |
11 to 14 V |
Ignition switch off |
Below 1 V |
NG |
REPAIR OR REPLACE HARNESS OR CONNECTOR (SKID CONTROL BUZZER ASSEMBLY - BATTERY) |
|
4. |
CHECK HARNESS AND CONNECTOR (SKID CONTROL BUZZER - FORWARD RECOGNITION CAMERA) |
(a) Disconnect the N38 skid control buzzer connector.
(b) Disconnect the F46 forward recognition camera connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection |
Condition |
Specified Condition |
---|---|---|
N38-1 (BZ) - F46-8 (BZ) |
Always |
Below 1 Ω |
N38-1 (BZ) or F46-8 (BZ) - Body ground |
Always |
10 kΩ or higher |
OK |
GO TO STEP 7 |
|
5. |
REPAIR OR REPLACE HARNESS OR CONNECTOR (SKID CONTROL BUZZER - FORWARD RECOGNITION CAMERA) |
(a) Repair or replace the harness or connector.
|
6. |
CHECK FOR DTCs (RADAR CRUISE 2) |
(a) Clear the DTCs.
Click here
(b) Perform the Active Test according to the display on the Techstream.
Click here
NOTICE:
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.
Powertrain > Radar Cruise2 > Active Test
Tester Display |
Measurement Item |
Control Range |
Diagnostic Note |
---|---|---|---|
Radar Cruise Stop Buzzer |
Skid control buzzer (stop sound) |
ON or OFF |
Buzzer can be heard |
Radar Cruise Approach Alarm Buzzer |
Skid control buzzer (approach sound) |
ON or OFF |
Buzzer can be heard |
(c) Check for DTCs.
Click here
Result |
Proceed to |
---|---|
DTC C1A4A is not output |
A |
DTC C1A4A is output |
B |
A |
END |
|
7. |
INSPECT SKID CONTROL BUZZER (CONFIRM BUZZER OPERATION) |
(a) Turn the ignition switch to ON.
(b) Check if the skid control buzzer is sounding.
Result |
Proceed to |
---|---|
The skid control buzzer does not sound when the ignition switch is ON |
A |
The skid control buzzer sounds continuously when the ignition switch is ON |
B |
B |
GO TO STEP 9 |
|
8. |
INSPECT SKID CONTROL BUZZER (UNIT INSPECTION) |
(a) Remove the skid control buzzer.
Click here
(b) Inspect the skid control buzzer.
Click here
Result |
Proceed to |
---|---|
Skid control buzzer is abnormal |
A |
Skid control buzzer is normal |
B |
B |
GO TO STEP 10 |
|
9. |
REPLACE SKID CONTROL BUZZER |
(a) Replace the skid control buzzer.
Click here
|
10. |
CHECK FOR DTCs (RADAR CRUISE 2) |
(a) Clear the DTCs.
Click here
(b) Perform the Active Test according to the display on the Techstream.
Click here
NOTICE:
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.
Powertrain > Radar Cruise2 > Active Test
Tester Display |
Measurement Item |
Control Range |
Diagnostic Note |
---|---|---|---|
Radar Cruise Stop Buzzer |
Skid control buzzer (stop sound) |
ON or OFF |
Buzzer can be heard |
Radar Cruise Approach Alarm Buzzer |
Skid control buzzer (approach sound) |
ON or OFF |
Buzzer can be heard |
(c) Check for DTCs.
Click here
Result |
Proceed to |
---|---|
DTC C1A4A is not output |
A |
DTC C1A4A is output |
B |
A |
END |
|
11. |
REPLACE FORWARD RECOGNITION CAMERA |
(a) Replace the forward recognition camera.
Click here
(b) Perform forward recognition axis adjustment.
Click here
|
12. |
CHECK FOR DTCs (RADAR CRUISE 2) |
(a) Clear the DTCs.
Click here
(b) Perform the Active Test according to the display on the Techstream.
Click here
NOTICE:
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.
Powertrain > Radar Cruise2 > Active Test
Tester Display |
Measurement Item |
Control Range |
Diagnostic Note |
---|---|---|---|
Radar Cruise Stop Buzzer |
Skid control buzzer (stop sound) |
ON or OFF |
Buzzer can be heard |
Radar Cruise Approach Alarm Buzzer |
Skid control buzzer (approach sound) |
ON or OFF |
Buzzer can be heard |
(c) Check for DTCs.
Click here
Result |
Proceed to |
---|---|
DTC C1A4A is not output |
A |
DTC C1A4A is output |
B |
A |
END (FORWARD RECOGNITION CAMERA WAS DEFECTIVE) |
|
13. |
REPLACE MILLIMETER WAVE RADAR SENSOR ASSEMBLY |
(a) Replace the millimeter wave radar sensor assembly.
Click here
(b) Adjust the millimeter wave radar sensor assembly.
Click here
|
14. |
CLEAR DTC (RADAR CRUISE 2) |
(a) Clear the DTCs.
Click here
NEXT |
END (MILLIMETER WAVE RADAR SENSOR ASSEMBLY WAS DEFECTIVE) |
Lost Communication With Vehicle Dynamics Control Module (U0122)
DESCRIPTION
This DTC is detected if communication is lost with the skid control ECU (brake
actuator assembly).
DTC No.
Detection Item
DTC Detection Condition
Trouble Area
U0122
Lost Communication with Vehicle Dynamics Contro ...
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