C1168 — Speed Wheel Sensor RR Coherency Fault #

The code description may vary depending on the manufacturer.

• RR Wheel Speed Sensor Signal Coherence Failure (Nissan)
• Right Rear Wheel Speed Sensor Circuit Incoherence (Ford)
• Rear Right Wheel Speed Sensor Plausibility Error (Renault)

Summary of Diagnostic Trouble Code C1168 #

The C1168 code relates to the right rear (RR) wheel speed sensor, an essential part of your vehicle’s anti-lock braking system (ABS). This code is set when the ABS control module detects an inconsistent or implausible signal from the RR wheel speed sensor compared to other wheels. Such a mismatch can prevent the ABS from accurately monitoring wheel rotation and ensuring optimal braking performance. The code is often triggered by electrical faults, sensor failure, or wiring issues. Addressing C1168 promptly is crucial not only for safety but also to prevent further damage to the braking system.

Common Symptoms for Code C1168 #

When the C1168 code is present, you will usually notice warning lights and changes in braking behavior. These symptoms range from subtle to obvious, often affecting the safety features tied to your ABS.

• ABS warning light illuminated on the dashboard
• Traction control or stability control warning lights
• Increased stopping distance or altered brake feel
• Loss of ABS function (wheels may lock during hard braking)
• Occasional pulsation in the brake pedal

Probable Causes for Code C1168 #

The underlying reasons for code C1168 typically center on the sensor, its wiring, or the ABS module. Here’s a breakdown of what most frequently triggers this trouble code, ranked by likelihood:

1. Faulty right rear wheel speed sensor
2. Damaged or corroded sensor wiring/connectors
3. Contaminated or misaligned sensor due to debris or rust
4. Faulty or damaged tone ring (reluctor ring) on the RR wheel hub or axle
5. Internal ABS control module fault (less common)

Step-by-Step Diagnosis for C1168 #

To accurately pinpoint the cause of code C1168, follow this methodical diagnostic approach. This process helps avoid unnecessary part replacements and ensures a proper fix.

• Confirm and Document the DTC: Use an OBD-II scanner to retrieve and record the code(s) present. Clear codes and see if C1168 returns after a short test drive.
• Visual Inspection: Carefully inspect the right rear wheel speed sensor, its wiring, and connectors for visible damage, corrosion, or disconnection.
• Check Sensor Alignment and Cleanliness: Ensure the sensor is properly seated and the tone ring (reluctor) is clean and free of debris or rust.
• Test Sensor Output: Using a multimeter, check the resistance and output signal of the RR wheel speed sensor. Compare readings to OEM specifications.
• Wiring Continuity Check: Test for continuity and shorts in the wiring harness leading from the sensor to the ABS module.
• Scan Other Wheel Speed Sensor Data: With a scan tool, monitor live wheel speed data while driving to compare readings from all sensors.
• Inspect the Tone Ring: Check for cracks, missing teeth, or deformation on the RR tone ring.
• Assess the ABS Module: If all components check out, consider possible internal faults in the ABS control module. Consult OEM-specific diagnostic procedures.

Possible Repairs for C1168 #

Resolving C1168 involves targeted repairs based on diagnostic findings. Address the most likely causes first to save time and expense.

• Replace the right rear wheel speed sensor if faulty
• Repair or replace damaged, frayed, or corroded wiring/connectors at the RR wheel sensor
• Clean and reposition the sensor or tone ring as needed
• Replace a cracked, missing, or damaged tone ring
• Replace or reprogram the ABS control module (rare; only after all other steps)

Is It Safe to Drive with Code C1168? #

Driving with code C1168 is not recommended if you depend on ABS for safe braking. While your regular brakes will keep working, ABS and associated safety features (traction/stability control) will likely be disabled. This means increased risk of wheel lockup and loss of control during emergency stops or on slippery surfaces. Have the issue diagnosed and repaired as soon as possible to ensure your vehicle’s safety systems are fully operational.

Vehicles Most Commonly Affected by C1168 #

While C1168 is a generic OBD-II code, it is particularly frequent on certain makes and models, often due to design or environmental factors.

• Nissan Altima, Maxima, Murano, and Rogue (various years)
• Ford Focus, Escape, and Fusion (specific model years)
• Renault Megane and Scenic
• Infiniti G35 and FX35
• Select Toyota and Lexus SUVs (less commonly)

Common Mistakes & Best Practices for C1168 #

When tackling code C1168, some pitfalls and shortcuts can lead to misdiagnosis or recurring faults. Following best practices ensures a lasting repair.

• Replacing the sensor without checking wiring or the tone ring can lead to repeat failures.
• Not using a scan tool to monitor live sensor data during a test drive may miss intermittent issues.
• Skipping a physical inspection for debris, rust, or misalignment at the sensor mounting point.
• Assuming the ABS module is faulty before exhaustively testing related components and wiring.
• Failing to clear the code and verify repair success with a follow-up scan/test drive.

Quick FAQ for C1168 #

Here are some quick answers to the most common questions about code C1168:

• Q: Will my brakes still work if I have code C1168?
  A: Yes, your base brakes will function, but ABS and related safety features may be disabled, increasing risk in emergency situations.
• Q: Can I fix C1168 myself?
  A: If you have basic mechanical skills and a multimeter, you can inspect and replace the sensor or wiring. For complex ABS module issues, consult a professional or the OEM’s repair procedures.