⌘K
HomeTrouble codesU3003
Diagnostic trouble code

U3003

3 owner reports and 98 manufacturer filings across 32 model years from Ford, Honda, Lincoln, Mazda.

NetworkManufacturer-specific98 manufacturer filings3 owner reports

Where U3003 shows up

Source: NHTSA manufacturer communications and complaints
Model yearFiled underBulletinsOwner reports
2020 Ford F-250 Super DutyElectrical System7
2020 Ford F-350 Super DutyElectrical System7
2021 Ford F-250 Super DutyElectrical System6
2021 Ford F-350 Super DutyElectrical System6
2020 Ford F-450 Super DutyElectrical System6
2022 Ford F-250 Super DutyElectrical System5
2022 Ford F-350 Super DutyElectrical System5
2021 Ford F-450 Super DutyElectrical System5
2016 Mazda CX-9Structure5
2022 Ford EscapeElectrical System4
2022 Ford F-450 Super DutyElectrical System4
2021 Ford EscapeElectrical System3
2020 Ford EscapeElectrical System3
2023 Ford MaverickElectrical System3
2022 Ford MaverickEngine And Engine Cooling3
2022 Lincoln CorsairElectrical System3
2021 Lincoln CorsairElectrical System3
2023 Ford EscapeHybrid Propulsion System2
2016 Ford FiestaPower Train2
2019 Ford Transit ConnectSteering2
2023 Lincoln CorsairHybrid Propulsion System2
2017 Mazda CX-5Structure2
2018 Mazda CX-9Structure2
2017 Mazda CX-9Structure2
2018 Mazda Mazda3Forward Collision Avoidance2
2026 Ford ExplorerElectrical System1
2018 Honda CR-VElectrical System1
2026 Lincoln AviatorElectrical System1
2021 Mazda CX-5Electrical System1
2021 Mazda CX-9Electrical System1
2020 Mazda CX-9Electrical System1
2019 Mazda CX-9Electrical System1

A model year appears here because the code is named in its record, not because every one of these vehicles sets it. Counts are mentions in the federal files, not failure rates — nobody publishes the denominator.

What it gets filed under

Electrical System 67Engine And Engine Cooling 7Hybrid Propulsion System 5Equipment 5Structure 5Unknown Or Other 2
Advertisement

What owners said

Source: NHTSA complaint database

Owners’ own words, one per nameplate, scrubbed of anything identifying. These are unverified reports filed with NHTSA — they are what was said, not a finding that it was true.

The contact had taken the vehicle to a non-manufacturer dealer who used a handheld scanner and retrieved the following codes: C1001 Type 97, U3003, and B13D3
2018 Mazda Mazda3at 31,321 milesApr 15, 2024NHTSA owner report

Manufacturer filings that name it

Source: NHTSA manufacturer communications

Service bulletins and campaigns whose filed summary names U3003. Quoting the document number at a service desk is often the fastest route to a diagnosis someone has already written down.

What U3003 means

Source: SAE J2012 / OBD-II

U3003 is a manufacturer-specific code: the second character is a 3, which under the OBD-II standard hands the definition to whoever built the vehicle. The same code can mean one thing on a Ford and something unrelated on a Hyundai. Any site that prints a single definition for it is guessing.

A stored code names the test that failed, never the part that caused it. It is the starting point of a diagnosis, not its conclusion — the same code has several possible causes and the cheap one is not always right.

Common questions about U3003

Source: NHTSA files and the OBD-II standard

Why does this page not define U3003?

Because it cannot be defined honestly. The second character of a trouble code says who owns its meaning, and a 1 or a 3 hands that to the manufacturer. Sites that print one definition for a manufacturer-specific code are showing you one automaker's meaning and hoping it is yours.

Can I keep driving with U3003 stored?

Nobody can answer that from the code alone, and a site that does is guessing. A steady light generally means the fault was logged and the vehicle is in a reduced-risk mode; a flashing light means stop soon, because a misfiring engine can destroy a catalytic converter in minutes. The safe read of this page is the mileage and the components, not permission.

Does a code mean the car is recalled?

No. Recalls are filed by campaign and matched by VIN, and none of them are triggered by a scan tool. If you want to know whether an open recall applies to one specific vehicle, check the VIN at nhtsa.gov/recalls — that is the only source that settles it.

Why do the counts here differ from other sites?

Because these are not estimates. Every number on this page is a count of documents in NHTSA's own files: manufacturer communications that name the code in their filed summary, and owner complaints that name it in the narrative. We do not model, weight or extrapolate them.

Will clearing the code fix it?

Clearing turns the light off and erases the freeze-frame data a technician would have used to work out what happened. If the condition is still there the code returns, usually within a few drive cycles, and the diagnosis now starts from less information than before.