C1139 — Wheel Speed Sensor Center Tone Ring Missing Tooth Fault #

The wording of this code may differ depending on the vehicle manufacturer.

• Wheel Speed Sensor Center Tone Ring Tooth Missing (Nissan)
• Missing Tooth Detected at Center Tone Ring (Ford)
• Tone Wheel Tooth Loss Detected (Chrysler)
• Central Tone Ring Tooth Error (Hyundai/Kia)

Summary of DTC C1139 #

The C1139 diagnostic trouble code (DTC) indicates that the vehicle’s electronic control unit (ECU) has detected a missing or damaged tooth on the center tone ring associated with a wheel speed sensor. The wheel speed sensor is a critical component of the anti-lock braking system (ABS) and traction control system (TCS), providing real-time data about wheel rotation. The tone ring (sometimes called a reluctor ring) is a toothed metal ring mounted on the wheel hub or axle, used by the sensor to determine wheel speed via magnetic pulses. If the ECU identifies an irregularity—such as a missing tooth—it may compromise the accuracy of ABS or traction control functions. This code can trigger warning lights on the dashboard and may impact vehicle safety systems. Prompt diagnosis and repair are advised to maintain full functionality of safety features.

Frequent Symptoms for DTC C1139 #

When a C1139 code is present, the vehicle may exhibit several noticeable symptoms. These symptoms are often related to the ABS and traction control systems, as they rely heavily on precise wheel speed data. In some cases, drivers may not notice any symptoms during normal driving, but warning lights and degraded safety features usually occur.

• ABS warning light illuminated on the dashboard
• Traction control warning light illuminated
• Loss of ABS or traction control function
• Unusual pulsing or feedback in the brake pedal (in rare cases)
• Intermittent or inconsistent activation of ABS during braking

Probable Causes for DTC C1139 #

The most common causes of a C1139 code are related to physical damage or misalignment of the tone ring or sensor. In some cases, wiring or electrical faults may also be the root of the problem. Here are the primary causes, listed in order of frequency:

1. Damaged or missing tooth on the tone ring (physical breakage or corrosion)
2. Debris or rust accumulation on the tone ring, interfering with sensor readings
3. Faulty wheel speed sensor (sensor head damaged or out of alignment)
4. Wiring or connector issues (corrosion, loose connections, or broken wires)
5. Improper installation or replacement of the tone ring or axle components

Step-by-Step Diagnosis for DTC C1139 #

Diagnosing a C1139 code requires a systematic approach, starting with visual inspection and progressing to more advanced testing if necessary. Always follow OEM (Original Equipment Manufacturer) procedures and safety precautions.

• Step 1: Check for other ABS or traction control codes using a professional scan tool.
• Step 2: Perform a thorough visual inspection of the wheel speed sensors and tone rings on all wheels—look for obvious damage, missing teeth, or heavy rust/debris.
• Step 3: Spin the affected wheel by hand and observe the tone ring for irregularities; compare with other wheels if possible.
• Step 4: Inspect the sensor wiring harness and connectors for signs of wear, corrosion, or loose connections.
• Step 5: Test the wheel speed sensor output using a multimeter or an oscilloscope, following OEM guidelines.
• Step 6: If no physical defects are found, verify tone ring alignment and sensor mounting according to OEM specifications.
• Step 7: Clear the code and test drive the vehicle to see if the code returns.

Possible Repairs for DTC C1139 #

Repairing a C1139 code typically involves addressing the specific cause discovered during diagnosis. Always use OEM-approved replacement parts and procedures to ensure safety and reliability.

• Replace the tone ring if teeth are missing or the ring is damaged beyond repair.
• Clean the tone ring to remove rust, debris, or buildup that could interfere with sensor readings.
• Replace or realign the wheel speed sensor if it is damaged or out of proper position.
• Repair or replace damaged wiring or connectors in the sensor circuit.
• Reinstall or correctly align the tone ring or related axle components if installation errors are found.

Can You Drive with DTC C1139? #

Driving is possible but not recommended with a C1139 code active. While the vehicle may operate normally under everyday conditions, the loss of functional ABS and traction control systems increases your risk—especially in adverse weather or emergency braking situations. Immediate repair is strongly advised to restore full safety system performance.

Most Commonly Affected Vehicles by DTC C1139 #

While C1139 can appear on a wide range of vehicles using modern ABS/TCS systems, it is most commonly reported on certain makes and models. If you own one of these vehicles, pay close attention to any warning lights related to ABS.

• Nissan Altima, Maxima, Pathfinder (2005–present)
• Ford F-150, Explorer, Escape (2008–2016)
• Chrysler 300, Dodge Charger, Dodge Ram (2007–2014)
• Hyundai Sonata, Santa Fe, Tucson (2010–2018)
• Kia Sorento, Sportage (2011–2017)

Common Mistakes & Best Practices for DTC C1139 #

When dealing with a C1139 code, certain pitfalls can delay or complicate repairs. Here are some common errors and best practices to keep in mind:

• Overlooking tone ring damage due to dirt or rust—always clean and inspect closely.
• Replacing the sensor without inspecting the tone ring—address the root cause, not just the symptom.
• Neglecting to check connector and wiring integrity—small faults can cause intermittent issues.
• Skipping OEM procedures—always follow manufacturer instructions for diagnosis and repair.
• Failing to clear codes and re-test after repairs—verify that the issue is resolved before returning the vehicle to service.

Quick FAQ for DTC C1139 #

Here are answers to some of the most common questions about the C1139 code:

• Q: Is C1139 a sensor or a tone ring problem?
  A: While the code references a tone ring issue, both the sensor and tone ring should be inspected. The code means the ECU detected irregular wheel speed signals, often due to a damaged or missing tone ring tooth, but sensor or wiring faults can also be involved.
• Q: Do I need to replace the entire axle if the tone ring is damaged?
  A: Not always. On some vehicles, the tone ring is separate and can be replaced. On others, it may be integrated into the axle or hub assembly, requiring more extensive replacement. Always consult OEM repair information for your specific model.