01 The EV Owner Who Charged For 100,000 Miles Tells Us What Th… • 02 The Mitsubishi Outlander PHEV: A Plug-in Hybrid SUV That Ch… • 03 The Hidden Damage Caused by “Perfect” City Driving • 04 The Wankel Rotary Engine: Compact, Smooth, and Powerful • 05 Is It Bad to Drive Long Distances and Turn Off the Engine I… • 06 Why Your Check Engine Light Won't Go Off: A Diagnostic Guide • 07 Gearbox Oil Change: When to Do It and Why It's Important • 08 How Naturally Aspirated Engines Differ From Turbo Engines • 09 Eco-Friendly and Powerful: The Best Fuel-Efficient SUVs for… • 10 P0065, P0066, and P0067: Air Assisted Injector Control •

DTC codes / C06xx · Brakes, steering and suspension / C0662

C0662Left Rear Wheel Speed Sensor B Circuit High

C0662 means the antilock brake system (ABS) control module has detected an abnormally high voltage on the signal circuit for the left rear wheel speed sensor, identified as sensor B. The module compares the sensor's output against expected values and flags the circuit as high when the voltage stays above the normal operating range, which can prevent the ABS and traction control from functioning correctly.

SystemChassis
Code typeGeneric (all makes)
SeverityMedium
Fix difficultyIntermediate
AreaBrakes, steering and suspension

Symptoms you may notice

  • ABS warning light illuminated on the dashboard, often with the traction control light
  • Traction control system disabled, which may be announced by a message on the driver information display
  • Often no symptoms besides the warning light, with normal braking performance in dry conditions
  • ABS may activate intermittently or at the wrong time, such as during light braking at low speed
  • Speedometer or odometer inaccuracy if the affected sensor also feeds the vehicle speed signal
  • Cruise control may become inoperative because it relies on wheel speed data

Common causes, most likely first

  1. Damaged or chafed sensor wiring harness, especially where it routes near the rear suspension or wheel well
  2. Corroded, loose, or water-intruded electrical connector at the left rear wheel speed sensor
  3. Failed left rear wheel speed sensor, either an internal short or a sensor that has lost its ground reference
  4. Metal debris or a damaged tone ring on the left rear hub causing an erratic signal that the module interprets as high voltage
  5. Faulty ABS control module, though this is less common and should be confirmed only after circuit testing
  6. Excessive air gap between the sensor and tone ring due to hub wear or a loose sensor mounting

How to diagnose and fix it

  1. Inspect the left rear wheel speed sensor connector and wiring for corrosion, chafing, or loose pins, and repair as needed
  2. Measure the sensor circuit voltage and resistance with a digital multimeter and compare to the manufacturer's specification
  3. Check the sensor's air gap and clean any metal debris from the tone ring on the left rear hub
  4. Perform a wiggle test on the harness while monitoring live wheel speed data to catch intermittent faults
  5. Replace the left rear wheel speed sensor if circuit tests confirm an internal fault
  6. Clear the code and verify the repair by test-driving while watching wheel speed PIDs for all four wheels
  7. If the code returns after sensor replacement, test the ABS module connector and circuit continuity back to the module

What a high voltage code really means

  • A high voltage reading on a wheel speed sensor circuit often comes from a broken ground or reference wire rather than a failed sensor, so testing the ground side before condemning the sensor saves money.
  • Debris stuck to the tone ring or a worn hub bearing can create a signal the module reads as high voltage, so a visual inspection of the hub area is essential before any parts are replaced.
  • This code does not always mean the sensor itself is bad; a short to voltage in the harness from a nearby circuit can set the same code and will not be fixed by a new sensor.
  • Intermittent C0662 codes that appear only after rain or a car wash point to water intrusion at the connector or a cracked sensor housing, which a dry-weather test drive will not reveal.
  • Some vehicles share the left rear wheel speed signal with the transmission control module or body control module, so a related communication or speedometer code may accompany C0662 and should not be ignored.

Can I keep driving with C0662?

The vehicle remains safe to drive in dry conditions because normal hydraulic braking is unaffected, but the ABS and traction control are disabled, so avoid hard braking, slippery surfaces, and towing until the fault is repaired.

Tools that help

Tools we recommend are in the Auto Veteran shop on Amazon. As an Amazon Associate we earn from qualifying purchases.

Guidance is general and written for all OBD-II vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.

Running on fumes Free guides aren't free to make. Top up the tank. Any amount, one time. Fuel the Garage