AutoCodes – GMC – C1227 GMC

C1227 GMC Code - Left Rear Excessive Wheel Speed Variation

Quick Answer

As the wheel spins, the wheel speed sensor produces an AC signal. Common causes include Faulty Hub Assembly (Left Rear Wheel Speed Sensor is part of hub assembly), Faulty Left Rear Wheel Speed Sensor, Left Rear Wheel Speed Sensor harness is open or shorted. 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: C1227 GMC indicates Left Rear Excessive Wheel Speed Variation.
Common causes: Common causes include Faulty Hub Assembly (Left Rear Wheel Speed Sensor is part of hub assembly), Faulty Left Rear Wheel Speed Sensor, Left Rear Wheel Speed Sensor harness is open or shorted.
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 2,536

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 27, 2020

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code C1227 GMC Description

As the wheel spins, the wheel speed sensor produces an AC signal. The Electronic Brake Control Module (EBCM) uses the frequency of the AC signal to calculate the wheel speed. The EBCM will set the OBDII code when the sensor is not to factory specifications.

OBDII Code C1227 GMC - Left Rear Excessive Wheel Speed Variation - AutoCodes.com — C1227 GMC Code - Left Rear Excessive Wheel Speed Variation

What does this mean?

What are the Possible Causes of the DTC C1227 GMC?

Faulty Hub Assembly (Left Rear Wheel Speed Sensor is part of hub assembly)
Faulty Left Rear Wheel Speed Sensor
Left Rear Wheel Speed Sensor harness is open or shorted
Left Rear Wheel Speed Sensor circuit poor electrical connection

How to Fix the DTC C1227 GMC?

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 C1227 GMC 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 C1227 GMC code?

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Need Help with the Code?

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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 C1227 GMC Code

1. What are the common symptoms of OBDII code C1227 GMC?

- Common symptoms include the ABS light being illuminated on the dashboard, traction control issues, and potential wheel speed sensor malfunction.

2. What could cause the OBDII code C1227 GMC to trigger?

- The code may be triggered by a faulty left rear wheel speed sensor, damaged wiring, or a problem with the ABS control module.

3. How can I diagnose the cause of OBDII code C1227 GMC at home?

- You can start by visually inspecting the left rear wheel speed sensor and its wiring for any damage. You can also use a diagnostic scanner to retrieve specific fault codes.

4. Is it safe to drive with OBDII code C1227 GMC present?

- It is not recommended to drive with this code present, as it can affect the vehicle's traction control and ABS system, potentially compromising your safety.

5. Can I reset the OBDII code C1227 GMC by disconnecting the battery?

- Disconnecting the battery may temporarily clear the code, but it is not a permanent solution. It is best to diagnose and repair the underlying issue causing the code.

6. How much does it typically cost to repair OBDII code C1227 GMC?

- The cost of repair can vary depending on the exact cause of the code, but it may involve replacing the left rear wheel speed sensor, repairing damaged wiring, or addressing issues with the ABS control module.

7. Can a DIY enthusiast repair OBDII code C1227 GMC themselves?

- Depending on your level of automotive expertise, you may be able to replace the left rear wheel speed sensor or address wiring issues yourself. However, complex ABS system repairs may require professional help.

8. Will OBDII code C1227 GMC cause my vehicle to fail an emissions test?

- This code is related to the ABS system and is unlikely to cause your vehicle to fail an emissions test. However, it is still important to address the issue promptly for safety reasons.

9. How long does it take to repair OBDII code C1227 GMC?

- The repair time can vary depending on the exact cause of the code and the availability of parts. In general, it may take a few hours to a full day to diagnose and repair the issue.

10. Can OBDII code C1227 GMC affect other systems in my vehicle?

- Yes, this code can affect the operation of the ABS system and traction control, potentially impacting the overall stability and safety of your vehicle.