Engine-Codes.com
Engine-Codes – Audi – P1851 Audi

P1851 Audi Code - CAN Data Bus ABS Incorrect Signal

Quick Answer

The P1851 Audi code indicates that there is an issue with the CAN (Controller Area Network) data bus signal related to the ABS (Anti-lock Braking System) in the vehicle. Common causes include Faulty ABS module, Damaged wiring or connectors in the CAN bus system, Malfunctioning ABS sensor. 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
P1851 Audi indicates CAN Data Bus ABS Incorrect Signal.
Common causes
Common causes include Faulty ABS module, Damaged wiring or connectors in the CAN bus system, Malfunctioning ABS sensor.
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.
What is this?
Table of contents Created and updated by William Orellana on Sep 07, 2024
💬 Need more help? Ask Auto Expert for instant answers — it's free!
AutoCodes App

Fix Your Car Smarter

Try the New AutoCodes App!

Get complete OBDII diagnostics, repair solutions, and cost estimates, plus AI chat support on demand.

AutoCodes App on Google Play

Code P1851 Audi Description

The P1851 Audi code indicates that there is an issue with the CAN (Controller Area Network) data bus signal related to the ABS (Anti-lock Braking System) in the vehicle. The CAN bus is a network that allows various control modules within the vehicle to communicate with each other. In this case, the ABS module is not receiving the correct signal on the CAN bus, which can lead to problems with the ABS system's functionality.

OBDII Code P1851 Audi - CAN Data Bus ABS Incorrect Signal
P1851 Audi Code - CAN Data Bus ABS Incorrect Signal

Common Causes of P1851 Audi

  1. Faulty ABS module.
  2. Damaged wiring or connectors in the CAN bus system.
  3. Malfunctioning ABS sensor.
  4. ECM issue affecting CAN bus communication.
  5. Corrosion or moisture in the ABS system components.

Symptoms of P1851 Audi

  1. ABS warning light illuminated on the dashboard.
  2. Inconsistent ABS system activation or braking performance.
  3. Loss of traction control functionality.
  4. Difficulty shifting gears in vehicles with automatic transmissions.
  5. Overall decrease in vehicle performance and drivability.

How to Fix P1851 Audi

  1. Perform a diagnostic scan to confirm the P1851 code and identify the specific cause of the issue.
  2. Inspect the ABS module, wiring, connectors, and sensors for any visible damage or corrosion.
  3. Test the ABS system components to ensure they are functioning correctly.
  4. Repair or replace any damaged components, such as the ABS module, wiring, or sensors.
  5. Clear the code from the vehicle's system and test drive to confirm that the issue has been resolved.

Cost to Fix P1851 Audi

The typical repair costs for addressing a P1851 Audi code can vary depending on the specific cause of the issue. In general, the cost of parts such as a new ABS module, wiring, or sensors can range from $200 to $800. Labor costs at auto repair shops typically range from $80 to $150 per hour, with the total repair time depending on the complexity of the issue. Overall, the total cost of repairing a CAN Data Bus ABS Incorrect Signal code may range from $300 to $1500, including parts and labor. It's advisable to check with local auto repair shops for a more accurate estimate based on the specific make and model of the vehicle.

Need more information about the P1851 Audi code?

Need more information on how to fix the P1851 Audi code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P1851 Audi code diagnosed by a professional: Find a repair shop in your area

About the author: William Orellana is a Master Mechanic and Mechanical Engineer with over 30 years of experience diagnosing and repairing vehicles. Learn more about his background.

Frequently Asked Questions about P1851 Audi Code

1. What does the OBDII code P1851 mean on an Audi?

Code P1851 indicates an issue with the CAN Data Bus, specifically an incorrect signal from the ABS (Anti-lock Braking System).

2. What are the common symptoms of code P1851 in an Audi?

Symptoms may include the ABS warning light illuminating, loss of ABS functionality, traction control issues, or erratic speedometer readings.

3. What causes the P1851 code to appear in an Audi?

Common causes include a faulty ABS module, damaged or corroded wiring in the CAN bus system, or communication errors between control modules.

4. Can I drive my Audi with the P1851 code?

While the vehicle may still be drivable, the ABS and traction control systems may not function properly, reducing safety in slippery conditions. It’s best to address the issue promptly.

5. How do I diagnose the P1851 code on an Audi?

Start by scanning for additional fault codes, inspecting the ABS module and wiring, and testing the CAN bus communication with a diagnostic tool.

6. What should I check if I get a P1851 code?

Inspect the ABS module, CAN bus wiring for damage or corrosion, and ensure all ground connections are secure.

7. Can a weak battery cause the P1851 code in an Audi?

Yes, a weak or failing battery can lead to communication errors on the CAN bus, potentially triggering the P1851 code.

8. How is the P1851 code repaired on an Audi?

Repairs may include fixing or replacing damaged wiring, repairing or replacing the ABS module, or updating control module software if needed.

9. What tools are needed to fix the P1851 code?

You’ll need an OBDII scanner, a multimeter, and possibly a CAN bus diagnostics tool to identify and resolve the issue.

10. Is the P1851 code a common problem in Audis?

While not extremely common, it can occur in older models or vehicles with wiring damage or ABS module issues.

Discuss the causes and fixes for P1851 Audi OBDII Code

Submit a New Comment

Code P1851 Audi comments

No comments found for this page.