OBD-II trouble code
U041F: Invalid Data Received From Electronic Throttle System Control Module "B"
A second throttle-control module ("B") is sending data the network doesn't believe. Rare hardware — mostly multi-throttle or specialized powertrains.
Quick facts
- System
- Network
- Category
- Network Communication
- Severity
- Medium severity
- Drivable
- Usually safe to drive short-term
- Repair cost range
- $100 – $900
- DIY difficulty
- Shop recommended
Browse every code in U0401–U0478, or start from the full code library.
What does U041F mean?
U041F flags implausible data arriving from electronic throttle system (ETS) control module "B" — the second throttle controller on vehicles that have one. That's uncommon hardware: most cars run their single electronic throttle from the PCM (faults there set P-codes like P2135 or U0408 for invalid data from throttle module "A"). A distinct "B" module appears on some multi-throttle engines, specialized powertrains, and certain manufacturer architectures — so the first diagnostic step is confirming what your specific vehicle actually has.
As an invalid-data (U04xx) code, the module is communicating; its content fails plausibility. The cause menu: a genuine fault in the throttle module or its sensors, supply voltage/ground problems corrupting its output, software mismatches after service, CAN wiring damage, or the module honestly relaying implausible readings from a failing throttle actuator.
Throttle data is safety-relevant, so where module "B" has authority over a throttle the engine actually depends on, expect a firm fallback while the code is active — reduced power or a capped opening. Where the second module serves a secondary or auxiliary throttle instead, the consequence can be far milder, which is one more reason the identification step comes first rather than last. Diagnosis follows the invalid-data playbook: basics (battery, grounds), then the sending module's own health and any throttle-position rationality codes stored alongside.
Common causes
- Poor supply voltage or ground corrupting the module's data
- Software/calibration mismatch after module or throttle service
- CAN wiring damage or interference
- Misidentified or manufacturer-specific usage — confirm against service data before anything is ordered
- Failing throttle actuator feeding the module implausible readings
- Fault within the ETS "B" module or its throttle position inputs
Symptoms
- Reduced power / limp mode
- Check engine light, possibly with throttle codes alongside
- Hesitation or capped throttle response
- Code stored in other modules
- Behavior may normalize between events
Diagnostic steps
- 1.Confirm from service data that your vehicle actually has a second throttle control module — this code is rare and make-specific.
- 2.Check battery, charging, and the module's grounds first; low voltage corrupts data before it kills communication.
- 3.Scan all modules for companion throttle codes (P0120-P0124, P2100-P2138) that identify the physical fault.
- 4.Check for TSBs/software updates for the throttle or ETS module.
- 5.Inspect CAN wiring to the module for damage.
- 6.Replace/program the module or throttle unit per findings; perform required relearns and road-test.
Repair cost
$100 – $900
Highly platform-dependent given the rare hardware. Grounds, connectors, and software updates sit at the low end; a throttle module or throttle unit with programming runs $300-$900. Accurate identification of the "B" module on your platform is half the job.
Estimate your repair
Run the numbers for your vehicle
Open the Repair Cost Estimator with control module replacement & programming preselected. Adjust labor rate and vehicle category to fit your situation.
DIY vs shop
Leave this one to a qualified shop. The barrier here is module programming, security access, and bus-level diagnosis that need manufacturer-grade scan tools and the credentials to use them. DIY attempts often produce a more expensive problem than the original code.