Reference meaning
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.
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.
Scan worksheet →Manufacturer communications
35Original wording in English
FORD
Some 2024-2026 Bronco vehicles may exhibit various TRM concerns when attempting first time installation of a dealer installed accessory TRM, including one or more of the following: TRM unable to be programmed -Trailer lights inoperative -DTC U2100 stored in the TRM. This may be due to any of the following conditions:-The incorre…
FORD
Some 2021-2026 F-150 vehicles may exhibit a U2100:00 diagnostic trouble code (DTC) for initial configuration incomplete stored in the trailer control module (TRM). This may be due to the vehicle having a Ford accessory trailer brake kit installed without being programmed following the included instructions. If the vehicle was bu…
LINCOLN
Some 2025 Aviator vehicles equipped with 28 radio speakers (minor feature code IDBBN) may have previously exhibited at least one of the following error messages in Ford Diagnosis and Repair System (FDRS) while programming the audio digital signal processing module (DSP):<br /><br /> * "Procedure Unsuccessful - ReadDTCs DTCs pres…
FORD
Some 2023-2025 F-Super Duty vehicles may display an error during replacement of the SCCM that contains the following message: "Reprogramming has failed, would you like to retry?". If this error is present, the SCCM will not complete PMI and may store diagnostic trouble codes (DTC) U2100 and/or U2101 in the SCCM. This may be due …
Check vehicle applicability
203A listed vehicle is a research lead. Confirm the engine, production range and software in the manufacturer's information.
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.