01 Understanding Car Wheel Shaking at Low Speeds: Causes and S… • 02 Inside the Three-Way Catalytic Converter: A Breakdown of It… • 03 Drivers Are Left Stunned After Discovering The Real Purpose… • 04 What Depth of Water Can I Drive Through With My Car? • 05 How to Save Gas with a Turbocharged Car • 06 How to Increase Horsepower in a Naturally Aspirated Engine • 07 U0002 High Speed CAN Communication Bus Performance • 08 Why Turning Off the Engine Immediately is Bad for Your Turb… • 09 Don't Panic! Here's What to Do When the Skidding Warning Li… • 10 Why Does My Car Go Faster Than the Speed Limit? •

DTC codes / U05xx · Network communication / U0552

U0552Invalid Data Received From Running Board Control Module B

U0552 is a communication fault indicating that a control module received invalid or missing data from the running board control module B over the vehicle's network. The running board control module B is responsible for operating the power-deployable running boards, and the code sets when its messages are corrupted, out of range, or absent when expected.

SystemNetwork
Code typeGeneric (all makes)
SeverityLow
Fix difficultyIntermediate
AreaNetwork communication

Symptoms you may notice

  • The service engine soon or traction control light may illuminate, often with no other noticeable symptoms.
  • Power running boards may fail to deploy or retract, or may move erratically.
  • The running board may stay stuck in one position, creating a step-in or clearance issue.
  • A warning message may appear on the driver information center indicating a running board system fault.
  • In some cases, the running boards may operate normally despite the stored code.

Common causes, most likely first

  1. Corroded, damaged, or loose wiring or connectors at the running board control module B or its network interface.
  2. A failing running board control module B due to water intrusion, impact, or internal electronic failure.
  3. Low battery voltage or a weak charging system causing modules to drop network messages.
  4. A faulty ground connection for the running board control module B or the network bus.
  5. Network communication bus faults, such as a shorted or open data line, affecting multiple modules.
  6. Aftermarket accessories or improper electrical repairs interfering with the module's data signals.

How to diagnose and fix it

  1. Perform a full battery and charging system test to rule out low voltage as the root cause.
  2. Inspect and clean the connectors and wiring at running board control module B, looking for corrosion or damage.
  3. Check the module's ground connection and repair any loose or corroded ground points.
  4. Use a scan tool to clear the code and verify whether it returns immediately or after a drive cycle.
  5. If the code persists, perform a network communication test to check for bus faults or other modules with communication errors.
  6. Substitute a known-good running board control module B if available, or perform a module swap test to confirm the fault.
  7. If all else fails, follow the manufacturer's diagnostic flow chart for U0552, which may involve oscilloscope testing of the data bus.

Running board module faults often misdiagnosed

  • A weak or failing battery is a common culprit for U-codes, including U0552, because low voltage can cause modules to send corrupted data.
  • Water intrusion into the running board control module B, often from road splash or clogged drains, can cause intermittent invalid data without any visible external damage.
  • The code may be set by a faulty network gateway or a problem with another module that shares the same data bus, not necessarily the running board module itself.
  • Aftermarket electrical accessories, such as trailer brake controllers or alarm systems, can introduce noise on the data bus and trigger communication codes.
  • Always check for technical service bulletins (TSBs) for the specific vehicle, as some manufacturers have known issues with running board module software or wiring harness routing.

Can I keep driving with U0552?

The vehicle is generally safe to drive because the fault affects a convenience system, but avoid using the running boards if they are stuck in a position that could cause injury or damage. Have the issue diagnosed soon to prevent further electrical problems.

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