U0401 on Ford
Invalid Data Received From ECM/PCM "A"
U0401 on Ford vehicles indicates invalid data received from ecm/pcm "a". Au7o has documented this code across 1 Ford model — most commonly on Maverick. This network code is set when a module on the data bus receives implausible or invalid data from engine/powertrain control module "A". It means the modules are communicating, but the information coming from the ECM/PCM does not make sense, indicating a data integrity or module problem rather than a total loss of communication. Because powertrain data is shared widely, this can disable systems like traction control, illuminate the check engine light, or even prevent starting. Diagnosis focuses on the ECM/PCM, its wiring, sensor inputs, and the bus.
Common Causes of U0401
- •Faulty ECM/PCM or internal software fault
- •Damaged, shorted, or corroded ECM/PCM wiring/connectors
- •One or more faulty sensors feeding the ECM/PCM
- •Low system or battery voltage / weak battery
- •Communication bus wiring fault
- •Poor ground or power supply to the module
- •Outdated module software requiring update
U0401 on Ford by Model
Ford Maverick(1 issue)
- HPCM Software Forces Vehicle into Neutral While Driving (Recall 24S33 / 24V-330)2022-2024
On affected 2022-2024 Maverick Hybrid trucks, a recent update to the Hybrid Powertrain Control Module (HPCM) software calibration may result in a forced neutral condition while driving, causing the vehicle to coast to a stop and automatically shift to Park, along with a wrench light, multiple warning messages, and an audible chime. After shifting back into Drive the vehicle enters a limp home mode with limited torque at speeds up to 30 mph. Ford's powertrain controls team determined that new Hybrid Transmission Internal Park Module (HTIPM) software released for use in service in January 2024 can result in DTCs U1010 and U1011 shortly after installation, and Ford was aware of 315 warranty claims in North America as of April 15, 2024. The recall covers approximately 8,727 vehicles (Maverick population ~8,369).
Looking for U0401 on a different make?
View U0401 across all makes →Frequently Asked Questions
What does U0401 mean on Ford?▼
U0401 stands for "Invalid Data Received From ECM/PCM "A"." This network code is set when a module on the data bus receives implausible or invalid data from engine/powertrain control module "A". It means the modules are communicating, but the information coming from the ECM/PCM does not make sense, indicating a data integrity or module problem rather than a total loss of communication. Because powertrain data is shared widely, this can disable systems like traction control, illuminate the check engine light, or even prevent starting. Diagnosis focuses on the ECM/PCM, its wiring, sensor inputs, and the bus. On Ford specifically, this code is documented across 1 model.
What causes U0401 on Ford vehicles?▼
Common causes on Ford: Faulty ECM/PCM or internal software fault, Damaged, shorted, or corroded ECM/PCM wiring/connectors, One or more faulty sensors feeding the ECM/PCM, Low system or battery voltage / weak battery, Communication bus wiring fault. Specific causes vary by model and year — see the per-model sections below.
How much does it cost to fix U0401 on a Ford?▼
Repair costs vary widely depending on the root cause and specific Ford model.
Which Ford models have U0401 documented?▼
Au7o has documented U0401 on 1 Ford model: Maverick.