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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