AutoCodes – Generic – C1040

C1040 Code - Rear Wheel Speed Comparative Performance

Quick Answer

The Anti-Lock Brake System (ABS) Module monitors the Rear Wheel Speed Sensor. Common causes include Faulty Rear Wheel Speed Sensor, Rear Wheel Speed Sensor harness is open or shorted, Rear Wheel Speed Sensor circuit poor electrical connection. 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: C1040 indicates Rear Wheel Speed Comparative Performance.
Common causes: Common causes include Faulty Rear Wheel Speed Sensor, Rear Wheel Speed Sensor harness is open or shorted, Rear Wheel Speed Sensor circuit poor electrical connection.
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.

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Code Popularity 18,016

How popular is this code, among other codes? Low

Repair Importance Level

Urgent (Diagnose now) (3 / 3)

Repair Difficulty Level

Advanced (Pro) (3 / 3)

What is this?

Table of contents Created and updated by William Orellana on Aug 06, 2020

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code C1040 Description

The Anti-Lock Brake System (ABS) Module monitors the Rear Wheel Speed Sensor. Each time excessive wheel speed sensor acceleration or deceleration is detected, a fault counter increments. If the fault counter exceeds a specified value, the DTC will set.

OBDII Code C1040 - Rear Wheel Speed Comparative Performance - AutoCodes.com — C1040 Code - Rear Wheel Speed Comparative Performance

What does this mean?

What are the Possible Causes of the DTC C1040?

Faulty Rear Wheel Speed Sensor
Rear Wheel Speed Sensor harness is open or shorted
Rear Wheel Speed Sensor circuit poor electrical connection

How to Fix the DTC C1040?

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.

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the C1040 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.

Need more information about the C1040 code?

Need more information on how to fix the C1040 code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the C1040 code diagnosed by a professional: Find a repair shop in your area

Information for Specific Makes

C1040 Chrysler — Rear Wheel Speed Comparative Performance
C1040 Dodge — Rear Wheel Speed Comparative Performance
C1040 Jeep — Rear Wheel Speed Comparative Performance
C1040 Suzuki — Stability Control System Function Failure

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 C1040 Code

1. What are the common symptoms of OBDII code C1040?

- Common symptoms of OBDII code C1040 include ABS warning light illuminated on the dashboard, traction control system malfunctions, and potential loss of stability control.

2. What does OBDII code C1040 indicate?

- OBDII code C1040 indicates a rear wheel speed comparative performance issue, which means there is a discrepancy in speed measurements between the rear wheels.

3. What are the possible causes of OBDII code C1040?

- Possible causes of OBDII code C1040 include faulty wheel speed sensors, damaged wiring or connectors, ABS module issues, or problems with the wheel bearings.

4. How can I diagnose OBDII code C1040?

- Diagnosing OBDII code C1040 involves using a professional OBDII scanner to read the code, checking the condition of the wheel speed sensors, inspecting wiring for damage, and testing the ABS system components.

5. Can I continue driving with OBDII code C1040 illuminated?

- It is not recommended to continue driving with OBDII code C1040 illuminated, as it can affect the performance of the ABS and traction control systems, potentially compromising vehicle safety.

6. How can I repair OBDII code C1040?

- Repairing OBDII code C1040 typically involves replacing faulty wheel speed sensors, repairing damaged wiring or connectors, addressing ABS module issues, and ensuring proper functioning of the wheel bearings.

7. Are there any DIY tips for fixing OBDII code C1040?

- DIY tips for fixing OBDII code C1040 include performing a visual inspection of the wheel speed sensors and wiring, checking and cleaning connectors, and ensuring proper installation of new components.

8. Will OBDII code C1040 cause my vehicle to fail an emissions test?

- OBDII code C1040 is related to ABS and traction control systems rather than emissions, so it is unlikely to cause your vehicle to fail an emissions test.

9. Is it safe to reset OBDII code C1040 with a scanner?

- While resetting OBDII code C1040 with a scanner may temporarily turn off the warning light, it is important to diagnose and repair the underlying issue to ensure proper functioning of the ABS and traction control systems.

10. How can I prevent OBDII code C1040 from recurring?

- To prevent OBDII code C1040 from recurring, it is essential to perform regular maintenance on your vehicle, including checking the condition of wheel speed sensors, inspecting wiring, and addressing any ABS system issues promptly.