DESCRIPTION
If the forward recognition camera detects a short to +B in the buzzer circuit, it will store DTC C1A4A12.
DTC No. | Detection Item | DTC Detection Condition | Trouble Area |
---|---|---|---|
C1A4A12 | Buzzer Circuit Short to Battery | While the skid control buzzer assembly is sounding, the forward recognition camera detects a short to +B in the buzzer circuit for 3 seconds or more. |
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WIRING DIAGRAM
CAUTION / NOTICE / HINT
NOTICE:
HINT:
Forward recognition camera adjustment can be performed by using either One Time Recognition or Sequential Recognition.
One Time Recognition: Click here
Sequential Recognition: Click here
PROCEDURE
1. | CHECK FOR DTCs |
(a) Clear the DTCs.
Chassis > Front Recognition Camera > Clear DTCs(b) Perform the Active Test according to the display on the Techstream.
NOTICE:
Perform the Active Test for 3 seconds or more.
HINT:
Performing the Active Test for 3 seconds or more causes DTC C1A4A12 to be stored if the DTC detection conditions are met.
Body Electrical > Pre-Collision System > Active Test Tester Display | Measurement Item | Control Range | Diagnostic Note |
---|---|---|---|
PCS Warning Buzzer | Sounds the skid control buzzer | Active / Not Active | Test possible with engine switch on (IG), vehicle stopped |
Tester Display |
---|
PCS Warning Buzzer |
(c) Check for DTCs.
Chassis > Front Recognition Camera > Trouble Codes Result | Proceed to |
---|---|
DTC C1A4A12 is not output | A |
DTC C1A4A12 is output | B |
A | ![]() | USE SIMULATION METHOD TO CHECK |
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2. | CHECK HARNESS AND CONNECTOR (SKID CONTROL BUZZER ASSEMBLY - FORWARD RECOGNITION CAMERA) |
(a) Disconnect the A15 skid control buzzer assembly connector.
(b) Disconnect the U14 forward recognition camera connector.
(c) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
Tester Connection | Switch Condition | Specified Condition |
---|---|---|
A15-1 (BZ) or U14-8 (BZ) - Body ground | Engine switch off | Below 1 V |
NG | ![]() | REPAIR OR REPLACE HARNESS OR CONNECTOR |
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3. | INSPECT SKID CONTROL BUZZER ASSEMBLY |
(a) Remove the skid control buzzer assembly.
Click here
(b) Inspect the skid control buzzer assembly.
Click here
OK | ![]() | REPLACE FORWARD RECOGNITION CAMERA |
NG | ![]() | REPLACE SKID CONTROL BUZZER ASSEMBLY |
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