C0040 on 2009-2020 Dodge Journey: Causes and Fixes for the Right Front Wheel Speed Sensor

What's Unique About the 2009-2020 Dodge Journey

While wheel speed sensor failures are common across many vehicle brands, the Dodge Journey's single generation (2009-2020) makes diagnosis consistent. The issue is almost always the sensor itself or the wiring harness near the wheel, which is exposed to the elements and constant movement from steering. Unlike some vehicles with multiple conflicting definitions for this code, on the Journey, C0040 reliably points to the right front wheel speed sensor circuit, simplifying diagnosis. The sensor is a standalone part, not integrated into the hub assembly, making replacement relatively straightforward compared to some other vehicles.

Generation note: The 2009-2020 Dodge Journey covers a single generation (JC49), but it received a significant facelift in 2011. The procedure for diagnosing and replacing the wheel speed sensor is consistent across all model years. The same OEM part number applies to the entire model run. The primary ABS-related fuses (F141, F156, F173) are located in the under-hood fuse box on 2011-2020 models.

Symptoms You May Notice

• ABS warning light is illuminated on the dashboard.
• Traction Control or Electronic Stability Control (ESC) light is on.
• Cruise control may be disabled.
• In rare cases, the speedometer may behave erratically.
• Brake pedal may pulsate at low speeds if the sensor signal is noisy or erratic before failing completely.

Most Likely Causes

1. Faulty Right Front Wheel Speed Sensor 🔴 High Probability The sensor is exposed to road debris, moisture, and heat from the brakes, leading to eventual internal failure. It is a very common failure point on many vehicles, including the Journey.
   How to confirm: Use an OBD-II scanner capable of reading ABS codes to watch the live data stream for the right front wheel speed sensor while driving. If the speed reads 0 or is erratic compared to the other wheels, the sensor is likely bad. A multimeter can also be used to check for resistance across the sensor's pins (disconnected); an open (infinite resistance) or shorted (zero resistance) reading indicates a bad sensor. Comparing the resistance value to the known-good sensor on the left side is a reliable check.
   Typical fix: Replace the right front wheel speed sensor. 🎬 Watch this step-by-step Dodge Journey ABS sensor replacement guide. The sensor is typically held into the steering knuckle by a single bolt.
   Est. part cost: $25-$100
2. Damaged Wiring or Connector 🟡 Medium Probability The wiring harness runs down the suspension and is subject to constant flexing with steering and suspension movement. This can cause the wires to break internally, even if the insulation looks intact. The connector itself is also prone to corrosion or damage from road debris.
   How to confirm: Visually inspect the entire length of the sensor's wiring from the wheel hub to the main harness connector in the fender well. Look for chafing, cuts, or corrosion. A common failure point is right at the pigtail connector; gently pulling on the individual wires may reveal an internal break if one stretches.
   Typical fix: Repair the damaged section of wire or replace the pigtail connector. 🎬 Watch how to diagnose and fix C0040 wiring issues. Ensure the harness is properly secured away from moving parts and has enough slack to accommodate suspension travel.
   Est. part cost: $15-$50
3. Damaged or Dirty Tone Ring ⚪ Low Probability The tone ring (or reluctor ring), which the sensor reads, is part of the wheel hub assembly. While durable, heavy rust, metallic debris from a failing wheel bearing, or physical damage can interfere with the sensor's reading.
   How to confirm: After removing the sensor, inspect the tone ring through the sensor mounting hole with a flashlight. Look for missing teeth, heavy rust buildup, or caked-on debris. Check for any play in the wheel bearing, as excessive movement can alter the sensor's air gap and cause an erratic signal.
   Typical fix: Cleaning the tone ring with a brush and brake cleaner may work temporarily. However, if the ring is damaged or the issue is caused by a bad wheel bearing, the entire wheel hub assembly will need to be replaced.
   Est. part cost: $100-$250

Rare But Worth Checking

• Faulty ABS Control Module: This is very rare. Before condemning the ABS module, all other possibilities (sensor, wiring, hub) must be exhaustively ruled out. A faulty module will typically set multiple other codes for different sensors or internal faults, not just C0040.

Diagnosis Steps

1. Connect an OBD-II scanner capable of reading ABS/Chassis codes to the vehicle.
2. Confirm that C0040 is the active or stored code. Note any other codes present, as multiple wheel speed codes could point to a module issue.
3. Use the scanner's live data function to monitor the speed of all four wheels while driving slowly (5-10 mph).
4. Verify that the Right Front wheel speed reads 0 mph, is significantly different from the other three wheels, or drops out intermittently.
5. Safely raise and support the front of the vehicle. Visually inspect the right front wheel speed sensor and its wiring harness for any obvious damage, such as cuts, chafing, or loose connections.
6. Follow the harness from the wheel hub up into the fender well, checking all mounting points and connectors. Pay close attention to the pigtail section that flexes with the steering.
7. If no visual damage is found, disconnect the sensor and test its resistance with a multimeter. An open circuit (infinite resistance) or short circuit (zero resistance) confirms a failed sensor. The most reliable resistance test is to compare the reading to the known-good sensor on the other front wheel; the values should be very close.
8. Alternatively, with the multimeter set to AC Volts, probe the sensor's two pins and spin the wheel by hand (about one revolution per second). A good sensor should generate a small voltage, typically over 100-200 millivolts. No voltage indicates a bad sensor.
🎬 See a video demonstration on how to test wheel speed sensors.
9. If the sensor tests good, check for voltage and ground at the harness connector (vehicle side). Then, perform a continuity test on the harness wires between the sensor connector and the main ABS module connector.
10. After replacing the faulty component, clear the codes with the scan tool. The warning lights should turn off automatically after a short drive cycle where the module confirms a good signal from all sensors.

Parts You'll Likely Need

• Front Right ABS Wheel Speed Sensor (OEM #5085822AD) — This is the most common failure point for the C0040 code. The sensor itself fails internally from heat, vibration, and moisture, leading to a loss of signal.
  Trusted brands: Mopar, Dorman, Standard Motor Products (SMP), Delphi, NTK
  OEM price range: $80-$120
  Aftermarket price range: $25-$70

Related Codes That Often Appear With This One

• C0035 (Left Front Wheel Speed Sensor Circuit)
• C0045 (Left Rear Wheel Speed Sensor Circuit)
• C0050 (Right Rear Wheel Speed Sensor Circuit)

Platform-Specific Known Issues

• Internal Wire Breakage in Harness: A common point of failure is an internal break in the wires within the sensor's pigtail harness, especially where it flexes. The outer insulation may look perfectly fine, but the copper wire inside has fractured, causing an intermittent or complete loss of signal. A diagnostic technique is to gently stretch the wires by hand; if a wire feels 'stretchy' or 'flimsy' like a rubber band, it is broken internally.

Mechanic-Grade Diagnostic Values

• ABS Wheel Speed Sensor Resistance — expected: No single specification is reliable. The best method is to compare the resistance to the sensor on the opposite wheel; values should be very similar. Some generic ranges cited are 800-2350 ohms, but real-world tests show this can vary widely.. Failure: A reading of 0 ohms (short circuit) or infinite/OL (open circuit) indicates a failed sensor. A value significantly different from the opposing sensor also indicates failure.
• ABS Wheel Speed Sensor AC Voltage Output — expected: Greater than 100-200 millivolts (0.1-0.2 VAC) when the wheel is spun by hand at approximately one revolution per second.. Failure: Little to no AC voltage is generated while spinning the wheel, indicating the sensor is not producing a signal.

Scan Tool Commands That Help

• wiTECH: ABS Initialization — This function, found under the ABS module's 'Misc Functions' tab, may be required after replacing certain ABS components or reprogramming the module to ensure the system is properly calibrated.

Wiring & Ground Locations

• Anti-Lock Brakes Module — Located in the engine compartment, at the lower right rear (passenger side).. This is the control unit that receives the signal from the right front wheel speed sensor. All circuit tests terminate here.
• G924a — A chassis ground point located at the lower right rear corner of the engine compartment, near the ABS module.. A poor ground connection at this point can cause various electrical issues for the ABS module, potentially leading to false sensor codes.
• Engine Mount Ground Strap — On the passenger side, a ground strap connects a body ground post (near the ABS connector) to the engine mount.. Owners have noted that the ABS module appears to be tied into this ground circuit. A loose or corroded connection here could potentially cause signal issues.
• ABS Fuses (2011-2020) — In the under-hood fuse box: F141 (40A Main ABS), F156 (10A Brake Module), and F173 (25A ABS Valves).. While a blown fuse typically causes a module communication error rather than a single sensor code, checking these is a fundamental step in any ABS diagnosis.

Real Owner Repair Stories

• YouTube channel 'Cars and Service' (2012 Chevrolet Impala (demonstrating a common failure pattern applicable to many vehicles)) — ABS light on with code C0040.
  ❌ Tried (didn't work) Previous shops had replaced the entire wheel hub/bearing assembly, which includes the sensor on that vehicle, but the code remained.
  ✅ What actually fixed it The wiring in the flexible pigtail harness near the sensor was broken internally, despite the outer insulation looking intact. Splicing in a new section of wire to repair the harness resolved the code. The mechanic noted this is a very common failure due to the constant movement of the wires when steering.

Diagnostic Flowchart

Other Known Issues on This Vehicle

Issues unrelated to this code that are worth knowing about as an owner of this generation:

• 3.6L Pentastar Left Cylinder Head Failure 🔴 High — Common on early models (2011-2013), causing misfires (P0300, P0302, P0304, P0306) and requiring head replacement. Less common on later years but still possible. (Ref: Chrysler Extended Warranty X56 (10 years / 150,000 miles).)
• 3.6L Pentastar Rocker Arm Failure ('Pentastar Tick') 🟠 Medium — A ticking noise from the top of the engine, often starting after 50,000 miles, is a sign of failing rocker arm bearings. Can lead to misfires and camshaft damage if ignored.
• 62TE Automatic Transmission Issues 🔴 High — Prone to solenoid pack failure, slipping, harsh shifting, and shuddering, often appearing between 75,000 and 120,000 miles.
• Premature Brake and Rotor Wear 🟠 Medium — A very common complaint among owners is faster-than-expected wear of brake pads and rotors, sometimes requiring replacement as early as 12,000-32,000 miles.
• Uconnect Infotainment System Glitches 🟡 Low — Owners frequently report issues with the Uconnect system, including frozen screens, Bluetooth connectivity problems, and total system failure. A temporary fix can sometimes be achieved by disconnecting the battery.
• Throttle Body Failure (2.4L Engine) 🟠 Medium — The throttle body on the 2.4L 4-cylinder engine is known to fail, causing stalling, erratic idle, and setting codes like P2110, P2111, and P2112.

Used vs. New Parts: Buying Guide for This Vehicle

When a used part is the smart pick: A used part is generally NOT recommended for the electronic wheel speed sensor itself due to its exposure to heat and elements, leading to a limited and unpredictable lifespan. However, sourcing a used wiring harness pigtail from a junkyard is a smart choice if your original connector is damaged or you've confirmed an internal wire break.

Donor-vehicle mileage cap: roughly under 60000 miles for the part to have meaningful remaining life.

What to inspect on the donor part:

• For a wiring pigtail, ensure the insulation is not brittle, cracked, or heat-damaged.
• Check that the connector pins are clean, straight, and free of any green or white corrosion.
• Gently flex the wires to ensure they are not stiff, which could indicate internal corrosion or impending failure.

OEM-only on this vehicle (don't cheap out):

• No parts for this specific repair are strictly OEM-only.

Aftermarket brands forum-validated for this vehicle:

• NTK (NGK's sensor brand, noted as an OE supplier for many vehicles)
• Standard Motor Products (SMP)
• Dorman
• Delphi

Real Owner Stories

Aggregated from forums and TSBs cited above. Mileages and costs reflect what owners reported in those sources.

Related OBD-II Codes

• P0300 — Random misfire code often associated with the 3.6L Pentastar engine's known cylinder head or rocker arm failures mentioned in the Journey's common issues.
• P0302 — Specific cylinder 2 misfire related to the 3.6L Pentastar left cylinder head failure (covered under Extended Warranty X56).
• P0304 — Specific cylinder 4 misfire related to the 3.6L Pentastar left cylinder head failure common on 2011-2013 models.
• P0306 — Specific cylinder 6 misfire related to the 3.6L Pentastar left cylinder head failure common on 2011-2013 models.

Frequently Asked Questions