U0431 Invalid Data Received From Body Control Module "A"
U0431 is a generic OBD2 network code. It means “Invalid Data Received From Body Control Module "A"” — the same on every make and model, because the definition comes from the SAE J2012 standard rather than from the carmaker.
Ask the AI about U0431 on your car- System
- Network (U)
- Code type
- Generic (SAE)
- Range
- U04xx
What the wording tells you
“Invalid data received” means messages from the named module arrive but fail the receiving module’s plausibility or integrity checks. The fault is usually in that module or one of its sensors; a software mismatch is the other common cause.
“A”: where a car has several identical components, SAE tells them apart with letters. Which physical part is “A” is defined by the manufacturer — check the service information for your car before replacing it.
Can I keep driving with U0431?
The rule of thumb for this area (invalid data between modules): It depends on the module: bad data from the engine, transmission, brakes or steering needs prompt attention; comfort functions can wait.
How U0431 breaks down
Network. Communication between the car’s control modules.
Generic code: defined by SAE, the same on every make.
Invalid data between modules.
The specific fault within this range.
Where to look: Invalid data between modules
Codes set when messages from another module arrive but make no sense — implausible values or failed integrity checks. The code names the module whose data was rejected.
Typical causes in this area
- A fault inside the sending module or in one of its sensors
- A software mismatch between modules
- Interference from damaged network wiring
Ask the AI about U0431 on your car
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Read and clear U0431 on your iPhone
Brimly reads stored, pending and permanent codes through a Bluetooth LE or Wi-Fi OBD2 adapter, explains each one offline from the same 2,693-code dictionary as this page, and clears them once the fault is fixed — each clear goes into the car’s service history with the codes it removed. OBD diagnostics are part of Brimly Forever, a one-time purchase; the PRO assistant explains a code for your exact car.
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Frequently asked
What does U0431 mean?
U0431 is a generic OBD2 network code. It means “Invalid Data Received From Body Control Module "A"” — the same on every make and model, because the definition comes from the SAE J2012 standard rather than from the carmaker.
Can I drive with U0431?
The rule of thumb for this area (invalid data between modules): It depends on the module: bad data from the engine, transmission, brakes or steering needs prompt attention; comfort functions can wait.
What causes U0431?
“Invalid data received” means messages from the named module arrive but fail the receiving module’s plausibility or integrity checks. The fault is usually in that module or one of its sensors; a software mismatch is the other common cause. Typical causes in this area: A fault inside the sending module or in one of its sensors; A software mismatch between modules; Interference from damaged network wiring.
How do I clear U0431?
Fix the cause first, then clear it with any OBD2 scanner or app. Once the fault is gone the car also clears it on its own: the check engine lamp goes off after the self-test passes on three drive cycles in a row, and the stored code ages out after about 40 warm-ups. Clearing without a repair only hides it for a while — and resets the readiness monitors an emissions inspection looks at.
Is U0431 the same on every car?
Yes. U0431 is a generic SAE J2012 code, so its definition is identical on every make and model. What differs is the cause behind it and the repair procedure, which depend on the engine — that’s why the assistant on this page asks for your car.
Guides
Definitions: the generic SAE J2012 codes from Brimly’s offline dictionary (data version 2026.09). Causes and advice are general guidance for all makes — the service information for your car has the last word.