C1AA3 Code - Vehicle Speed Sensor Circuit
Quick Answer
For vehicles with Lane Departure Alert System: The Lane Departure Warning Camera receives vehicle speed signals from the Skid Control ECU (Brake Actuator Assembly) via Controller Area Network (CAN) communication to control the lane departure alert system. Common causes include Faulty Vehicle Stability Control System, Faulty Skid Control ECU (Brake Actuator Assembly), Faulty Forward Recognition Camera. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
- What it means
- C1AA3 indicates Vehicle Speed Sensor Circuit.
- Common causes
- Common causes include Faulty Vehicle Stability Control System, Faulty Skid Control ECU (Brake Actuator Assembly), Faulty Forward Recognition Camera.
- Severity
- High - diagnose this code as soon as possible.
- Can I drive?
- Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
Code C1AA3 Description
For vehicles with Forward Recognition Camera System: The Forward Recognition Camera receives vehicle speed signals from the Skid Control ECU (Brake Actuator Assembly) (brake actuator assembly). If the Skid Control ECU (Brake Actuator Assembly) receives a Vehicle Speed Sensor malfunction signal, it informs the Forward Recognition Camera via CAN communication, and DTC C1AA3 is stored.
For vehicles with Lane Departure Alert System (W/ Steering Control): The Forward Recognition Camera receives vehicle speed signals from the Skid Control ECU (Brake Actuator Assembly). If the Skid Control ECU (Brake Actuator Assembly) receives a Vehicle Speed Sensor malfunction signal, it informs the Forward Recognition Camera via CAN communication, and DTC C1AA3 is stored.
What are the Possible Causes of the DTC C1AA3?
- Faulty Vehicle Stability Control System
- Faulty Skid Control ECU (Brake Actuator Assembly)
- Faulty Forward Recognition Camera
- Faulty Lane Departure Warning Camera (For vehicles with Lane Departure Alert System)
How to Fix the DTC C1AA3?
Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.
Code Tech Notes
If the Forward Recognition Camera has been replaced with a new one, be sure to perform Recognition Camera/Target Position Memory and Recognition Camera Axis Adjust.
What is the Cost to Diagnose the Code?
Labor: 1.0
To diagnose the C1AA3 code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.
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Information for Specific Makes
- C1AA3 Lexus — Vehicle Speed Sensor Circuit
- C1AA3 Toyota — Vehicle Speed Sensor Circuit
Frequently Asked Questions about C1AA3 Code
1. What does the OBDII code C1AA3 mean?
C1AA3 indicates a malfunction in the Vehicle Speed Sensor (VSS) circuit, which monitors and reports the vehicle's speed to the engine control module (ECM) and other systems.
2. What are the common symptoms of code C1AA3?
Symptoms may include erratic or non-functional speedometer, issues with cruise control, poor transmission shifting, and activation of warning lights such as ABS or Check Engine.
3. What causes the C1AA3 code to appear?
Common causes include a faulty vehicle speed sensor, damaged wiring or connectors in the VSS circuit, or issues with the ECM receiving or interpreting the signal.
4. Can I drive with the C1AA3 code?
While the vehicle may still function, driving with this code can lead to unreliable speed data, affecting systems like transmission shifting and cruise control, and may pose a safety risk.
5. How do I diagnose the C1AA3 code?
Start by inspecting the VSS and related wiring for damage or loose connections. Use a multimeter to test the sensor and its circuit. A scan tool can help confirm the issue.
6. How is the C1AA3 code repaired?
Repairs may involve replacing the faulty vehicle speed sensor, repairing or replacing damaged wiring or connectors, or reprogramming or replacing the ECM if necessary.
7. How much does it cost to fix the C1AA3 code?
The cost can range from $100 to $300 for sensor replacement, with additional costs for wiring repairs or ECM replacement if required.
8. Can a faulty ABS sensor cause the C1AA3 code?
No, the C1AA3 code specifically relates to the Vehicle Speed Sensor circuit. However, similar symptoms may arise if ABS-related sensors fail, so they should also be inspected if necessary.
9. What tools do I need to troubleshoot the C1AA3 code?
Useful tools include an OBDII scanner, multimeter, wiring diagrams, and possibly an oscilloscope to test the VSS signal.
10. Will clearing the C1AA3 code fix the problem?
Clearing the code may turn off the warning light temporarily, but the issue will return unless the underlying cause is properly repaired.
Discuss the causes and fixes for C1AA3 OBDII Code
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