Lexus NX: Buzzer Circuit Short to Battery (C1A4A12)
DESCRIPTION
If the forward recognition camera detects a short +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 is sounding, the forward recognition camera detects a short to +B in the buzzer circuit for 3 seconds or more. |
|
WIRING DIAGRAM
CAUTION / NOTICE / HINT
NOTICE:
- Inspect the fuses for circuits related to this system before performing the following procedure.
- When replacing the forward recognition camera, always replace it with a new one. If a forward recognition camera which was installed to another vehicle is used, the information stored in the forward recognition camera will not match the information from the vehicle. As a result, a DTC may be stored.
-
If the forward recognition camera has been replaced with a new one, be sure to perform forward recognition camera adjustment.
HINT:
Forward recognition camera adjustment can be performed by using either One Time Recognition or Sequential Recognition.
One Time Recognition: Click here
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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 power 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 | .gif) | USE SIMULATION METHOD TO CHECK |
|
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| 2. | CHECK HARNESS AND CONNECTOR (SKID CONTROL BUZZER - FORWARD RECOGNITION CAMERA) |
(a) Disconnect the I36 skid control buzzer connector.
(b) Disconnect the T18 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 |
|---|---|---|
| I36-1 (BZ) or T18-8 (BZ) - Body ground | Power switch off | Below 1 V |
(d) Connect the T18 forward recognition camera connector.
(e) Connect the I36 skid control buzzer connector.
| NG | | REPAIR OR REPLACE HARNESS OR CONNECTOR (SKID CONTROL BUZZER - FORWARD RECOGNITION CAMERA) |
|
| 3. | INSPECT SKID CONTROL BUZZER |
(a) Remove the skid control buzzer.
Click here
(b) Inspect the skid control buzzer.
Click here
| OK | | REPLACE FORWARD RECOGNITION CAMERA |
| NG | | REPLACE SKID CONTROL BUZZER |
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SEE MORE:
Inspection
INSPECTION PROCEDURE 1. INSPECT FRONT LOWER BALL JOINT ASSEMBLY LH (a) Inspect the turning torque of the ball joint. (1) Secure the front lower ball joint in a vise using aluminum plates. (2) Install the nut to the front lower ball joint stud. (3) Move the stud back and forth several times. Using
Precaution
PRECAUTION PRECAUTION FOR DISCONNECTING CABLE FROM NEGATIVE AUXILIARY BATTERY TERMINAL NOTICE: When disconnecting the cable from the negative (-) auxiliary battery terminal, perform steering angle sensor zero point calibration after the cable is reconnected. Click here PRECAUTIONS FOR LANE TRACING
