HomeU300A · Code meaning and manufacturer information
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U300A

Code meaning and manufacturer information

U300A

What does this code mean?

The wording below belongs to the named make and communication. Match the complete code, reporting module, model year and engine before applying it.

A code identifies a detected condition, not a part that must automatically be replaced.

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A listed vehicle is a research lead. Confirm the engine, production range and software in the manufacturer's information.

Manufacturer communications

3

Original wording in English

9100525

RAM

Reported code forms U300A-29

"Base led headlamp RT 25 MY HDCC Ignition DTC (U300A-29 Ignition Switch - Signal Invalid) in stored state for SLML and SLMR. All headlamps on the Heavy Duty with SW 24.43.00(Premium) or 24.44.00(Base) will show a…

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SSM 52606

FORD

Reported code forms U300A:01

Some 2023-2024 F-Super Duty vehicles equipped with a keyed ignition may exhibit a "Vehicle May Not Start/Restart Service Now" message in the instrument panel cluster (IPC) with diagnostic trouble code (DTC) U300A:01…

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Check vehicle applicability

12

A listed vehicle is a research lead. Confirm the engine, production range and software in the manufacturer's information.

MakeModelModel year
FordF-250 SD2024
FordF-250 SD2023
FordF-350 SD2024
FordF-350 SD2023
FordF-450 SD2024
FordF-450 SD2023
FordF-550 SD2024
FordF-550 SD2023
Ram25002025
Ram35002025
Ram45002025
Ram55002025

Before replacing a part

Record codes and freeze-frame data. Check battery condition, related codes and visible wiring or hose damage. Follow the vehicle's diagnostic procedure and test results before replacing parts.

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Can I keep driving?

A code alone cannot establish whether driving is safe. A flashing malfunction light, severe shaking, overheating, oil-pressure warning or loss of braking or steering needs prompt attention. Stop in a safe place and seek assistance when control or engine safety is affected. Follow the vehicle handbook.