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DTC codes / U04xx · Invalid data received from a module / U041F

U041FInvalid Data Received From Throttle Actuator B Control Module

U041F is a communication fault where the engine control module (ECM) or another network module receives invalid or missing data from the throttle actuator B control module over the vehicle's controller area network (CAN) bus. The computer has detected that the messages from the throttle actuator control module are either absent, corrupted, or outside the expected range for a set period, so it flags the module as unreliable.

SystemNetwork
Code typeGeneric (all makes)
SeverityMedium
Fix difficultyProfessional
AreaInvalid data received from a module

Symptoms you may notice

  • The check engine light or electronic throttle control warning light illuminates steadily.
  • The engine may enter limp mode, limiting power and engine speed to a low threshold.
  • The accelerator pedal may feel unresponsive or delayed when pressed.
  • The idle speed may be erratic or higher than normal.
  • The vehicle may hesitate or stumble during acceleration.
  • Often no symptoms besides the warning light, especially if the fault is intermittent.

Common causes, most likely first

  1. A weak or failing battery, or poor battery terminal connections, causing low voltage to the throttle actuator control module.
  2. Corroded, loose, or damaged wiring and connectors in the CAN bus circuit between the ECM and the throttle actuator control module.
  3. A faulty throttle actuator control module itself, often due to internal electronic failure or water intrusion.
  4. A failing electronic throttle body (actuator) that sends implausible position feedback to its control module.
  5. Software or calibration issues in the ECM or throttle actuator control module requiring a reflash or update.
  6. A shorted or open CAN bus wire, or a failed terminating resistor in the network, disrupting communication.
  7. Aftermarket electronic accessories improperly wired into the CAN bus, causing signal interference.

How to diagnose and fix it

  1. Perform a battery and charging system test, including load testing and checking terminal cleanliness and tightness.
  2. Use a scan tool to read all stored codes and freeze-frame data, then clear codes and test-drive to see if U041F returns.
  3. Visually inspect the throttle actuator control module connectors and the CAN bus wiring for corrosion, chafing, or loose pins.
  4. Measure CAN bus voltage and resistance at the diagnostic link connector (DLC) to verify network integrity and rule out wiring faults.
  5. Check for technical service bulletins (TSBs) or software updates for the ECM and throttle actuator control module, and reflash if applicable.
  6. Substitute a known-good throttle actuator control module or throttle body, if accessible, to confirm whether the module is the source.
  7. If wiring and power are confirmed good, replace the throttle actuator control module and perform any required adaptation or calibration procedure.

What most technicians overlook with U041F

  • A weak battery is the most common root cause of U041F, yet many technicians replace the throttle actuator module first without testing voltage under load.
  • The code can be set by a momentary voltage dip during cranking, so it may reappear only after the vehicle sits overnight or in cold weather.
  • Corrosion inside a connector that looks fine from the outside can interrupt CAN bus communication, so always back-probe terminals and check for water intrusion.
  • U041F does not always mean the throttle actuator control module is defective; a failed ECM or a faulty CAN bus gateway can also prevent valid data from reaching the module.
  • Aftermarket alarms, remote starters, or phone chargers plugged into the data link connector can introduce noise on the CAN bus and trigger communication codes like this one.

Can I keep driving with U041F?

You can usually drive the vehicle to a repair shop, but expect reduced engine power and possible limp mode, so avoid highways and heavy traffic. If the engine stalls or the throttle becomes completely unresponsive, pull over safely and have the vehicle towed.

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.

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