C0513 on 2015-2016 Ram ProMaster City: Wheel Speed Rationality Causes and Fixes

What's Unique About the 2015-2016 Ram PROMASTER CITY

For the Ram ProMaster City, this specific code is frequently linked to a software issue rather than a direct hardware failure. Ram issued technical service bulletin #18-063-17 REV. A to address this 'rationality' problem, where the control module's sensitivity was too high and could set false codes. The fix often involves a simple software reflash at a dealership to update the ABS module's calibration, a solution that is less common for wheel speed sensor codes on other vehicles.

Diagnostic Flowchart

Tap your situation to follow the diagnostic path that matches what you're seeing on this vehicle.

Symptoms You May Notice

• ABS warning light is illuminated on the dashboard
• Traction Control or Electronic Stability Control (ESC) warning light is on
• The 'Hill Holder' system may become unavailable
• Cruise control may be disabled

Most Likely Causes

1. ABS Control Module Software Requires Update 🔴 High Probability → Shop ABS Control Module Ram released TSBs #18-063-17 REV. A and #18-008-16 REV. B specifically to correct overly sensitive rationality checks within the ABS module software for this and other wheel speed sensor codes. This is the most common and well-documented cause for this specific vehicle and code.
   How to confirm: A Ram dealership or a well-equipped independent shop using a tool like wiTECH can check the current software version of the ABS module and determine if the update specified in the TSB has been applied.
   Typical fix: Flashing the ABS control module with the updated software. This procedure reprograms the module to be less sensitive to minor signal deviations.
   Est. part cost: $0
2. Faulty Right Rear Wheel Speed Sensor 🟡 Medium Probability → Shop ABS Wheel Speed Sensor Like any vehicle, wheel speed sensors are exposed to heat, moisture, and debris, which can cause them to fail over time. If the software update doesn't resolve the issue, the sensor itself is the next logical point of failure.
   How to confirm: Use a scan tool to monitor live data from all four wheel speed sensors while driving. If the right rear sensor reads erratically, drops to zero, or doesn't match the others, the sensor is likely bad. You can also test the sensor's internal resistance with a multimeter if specifications are available, though an oscilloscope is the most accurate tool.
   Typical fix: Replace the right rear wheel speed sensor. This involves removing the wheel, potentially the brake caliper and rotor, unbolting the old sensor, and installing the new one.
   Est. part cost: $35-$90
3. Damaged Wiring or Connector ⚪ Low Probability Wiring harnesses can be susceptible to damage from road debris, improper repairs (e.g., unsecured after previous work), or water intrusion, especially at the connectors.
   How to confirm: Visually inspect the wiring harness leading to the right rear wheel speed sensor for any signs of chafing, breaks, corrosion, or being improperly routed. Check the connector for bent pins, moisture, or debris. A multimeter can be used to check for continuity and shorts between the sensor connector and the ABS module.
   Typical fix: Repair the damaged section of the wiring harness or clean/replace the connector.
   Est. part cost: $5-$50

Rare But Worth Checking

• Damaged Tone Ring: The tone ring, which the sensor reads, is part of the wheel hub/bearing assembly. If it becomes cracked, rusted, or contaminated with metallic debris, it can cause erratic signals. This usually requires replacing the entire wheel hub assembly.
• Faulty ABS Control Module: → Shop ABS Control Module While rare, the ABS module itself can fail internally due to hardware or memory corruption. This should only be considered after all other possibilities, including the software update, sensor, and wiring, have been thoroughly ruled out. One owner on a forum reported a shop replaced the module multiple times without success, indicating it's often misdiagnosed.

Diagnosis Steps

1. Check for Technical Service Bulletins (TSBs). Confirm with a dealer if TSB #18-063-17 REV. A or #18-008-16 REV. B applies and has been performed. If not, this is the first and most likely fix.
2. Connect an OBD-II scanner capable of reading ABS codes and live data.
3. Monitor the wheel speed readings from all four sensors while driving. Observe the value for the 'Right Rear Wheel Speed Sensor'.
4. If the right rear sensor's reading is erratic, drops out, or is clearly different from the other three, proceed with a physical inspection.
5. Raise and secure the vehicle. Visually inspect the right rear wheel speed sensor and its wiring harness for any obvious damage, corrosion, or loose connections. Pay close attention to the routing of the harness to ensure it's not rubbing on suspension or chassis components.
6. If the wiring looks good, remove the sensor and inspect it for physical damage or metallic debris on the magnetic tip.
7. Inspect the tone ring on the wheel hub assembly through the sensor mounting hole. Look for cracks, missing teeth, or heavy rust/debris.
8. If all physical components appear intact, and the software is up to date, the sensor itself is the most likely culprit. Replace the right rear wheel speed sensor.
9. If the problem persists after replacing the sensor, perform a continuity and short-to-ground test on the wiring harness from the sensor connector to the ABS module connector.
10. If all other steps fail, the ABS control module may be faulty, but this is the least likely cause and should be the last resort.

Parts You'll Likely Need

• Rear ABS Wheel Speed Sensor (OEM #68437016AA) — If the issue is not software-related, the sensor itself is the most common hardware failure point for this code. This part number appears to be used across several Ram ProMaster models and years.
  Trusted brands: Mopar, Dorman, Standard Motor Products, Holstein
  OEM price range: $50-$90
  Aftermarket price range: $30-$60

Related Codes That Often Appear With This One

• C050D — This is the code for the Left Rear Wheel Speed Signal Rationality. The TSBs mention these codes together, suggesting the software issue can affect multiple sensors.
• C0507 — This is the code for the Right Front Wheel Speed Signal Rationality, also mentioned in the same TSBs.
• C0501 — This is the code for the Left Front Wheel Speed Signal Rationality, also mentioned in the same TSBs.

Technical Service Bulletins (TSBs) & Recalls

• 18-063-17 REV. A: Addresses wheel speed signal rationality codes (C0501, C0507, C050D, C0513) with a Powertrain Control Module (PCM) software update. This is the primary TSB for this issue.
• 18-008-16 REV. B: Also addresses wheel speed signal rationality codes, including C0513, with a software enhancement.

Platform-Specific Known Issues

• The 2015-2016 Ram ProMaster City is subject to TSBs #18-063-17 REV. A and #18-008-16 REV. B, which indicate that the ABS module may incorrectly flag a rationality fault. The prescribed fix is a software update, not necessarily a part replacement.
• As a vehicle based on a Fiat platform, owners may benefit from using advanced diagnostic software like AlfaOBD or Multiecuscan, which can offer dealer-level diagnostics for FCA vehicles.

Mechanic-Grade Diagnostic Values

• Voltage at sensor connector — expected: At least 10.5V, ideally close to battery voltage (12V+) with key on, engine off.. Failure: No voltage at the connector points to a wiring or ABS module issue upstream from the sensor.
• Sensor resistance with a multimeter — expected: Varies by sensor type (passive vs. active). Passive sensors may show a resistance in the kilo-ohm range.. Failure: A reading of zero or infinite ohms suggests a failed passive sensor. However, a 'correct' resistance reading does not guarantee the sensor is good, as a new, working sensor may have the same resistance as the old, faulty one. Active sensors should not be resistance tested.

Scan Tool Commands That Help

• AlfaOBD / Multiecuscan: ABS Live Data Monitoring & Fault Clearing — These aftermarket tools, paired with the correct OBD2 adapter, can access the ABS module on Fiat-Chrysler platforms to read live wheel speed data from all four sensors, read/clear chassis codes, and perform system tests, similar to dealer tools.
• AlfaOBD / Multiecuscan: Proxi Alignment Procedure — If the ABS module or other major electronic components have been replaced, a Proxi (or Proxy) alignment may be needed to ensure all vehicle modules recognize each other. An incorrect alignment can sometimes trigger ABS/ESP faults.

Wiring & Ground Locations

• Right Rear Wheel Speed Sensor Wires — In the harness running from the right rear wheel hub to the ABS control module.. Based on wiring diagrams for other Ram trucks, the wire colors are potentially Dark Green/Yellow and Dark Green/Violet. These wires carry the signal and power; a break or short in either will cause code C0513. This information is a guideline, and wire colors should be verified.
• Harness Chafe Point — On other Ram trucks, a common location for wiring damage is in the harness loom where it runs above the fuel tank and along the frame rail.. Vibrations and debris can cause wires within the main harness to chafe and break over time, leading to an open circuit that is difficult to find visually. A continuity test from the sensor connector to the ABS module connector is required to confirm.

Real Owner Repair Stories

• Fiat Forum thread on a platform-mate Fiat Doblò (Fiat Doblò (shares platform with ProMaster City)) — ABS light illuminated on the dashboard.
  ❌ Tried (didn't work) Replacing the wheel speed sensor with a new aftermarket part., Cleaning and tightening the ABS module connector pins., Splicing in a new harness-side connector., Swapping in a known-good used ABS module.
  ✅ What actually fixed it The owner was convinced the wiring or module was bad because the sensor was new. After exhausting all other options, they replaced the *new* aftermarket sensor with another new sensor from a *different manufacturer*, which finally solved the problem. The first new part was faulty out of the box.

"I Checked Everything" — The Actual Cause

• In a similar ProMaster, persistent wheel speed sensor codes were traced to an incorrect wheel hub assembly being installed. All electrical tests on the sensor and wiring passed, but the tone ring integrated into the new hub had a different diameter, creating too large of an air gap for the sensor to read the signal properly. The fix was to install the correct Mopar hub assembly with the proper tone ring dimensions.

When the Usual Fixes Don't Work

• While replacing the sensor is a common fix, it's not foolproof. A documented case on a platform-mate vehicle showed that an owner replaced the sensor, but the code persisted because the new aftermarket sensor was also defective. The problem was only resolved by using another new sensor from a different, higher-quality brand. This underscores the importance of not immediately ruling out a 'new' part as the potential cause of the problem.