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Ford U0100:00

Follow the Service Procedure steps to correct the condition on vehicles that meet all of the following criteria: • 2021 Mustang Mach-E • Built on or befo

Common search variants: U010000 · U0100-00 · U0100 00 · U0100_00 · Search ignores case and common separators.

DriveNot yet established by verified evidence.
ChargeNot yet established by verified evidence.
ServiceContact a Ford dealer or qualified service facility to determine whether TSB 21-2405 applies and to perform the specified GSM reprogramming procedure.
Confidence95%

Quick answer

For certain U.S. 2021 Ford Mustang Mach-E vehicles built on or before September 9, 2021, U0100:00 may be stored in the gear shift module (GSM) as covered by Ford TSB 21-2405. The bulletin identifies GSM software as the cause of the covered condition and directs GSM reprogramming through its Service Procedure.

This page separates verified manufacturer/regulator evidence from supporting material. Unsupported causes, repairs or safety conclusions are not guessed.

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1. What does U0100:00 mean?

For certain U.S. 2021 Ford Mustang Mach-E vehicles built on or before September 9, 2021, U0100:00 may be stored in the gear shift module (GSM) as covered by Ford TSB 21-2405. The bulletin identifies GSM software as the cause of the covered condition and directs GSM reprogramming through its Service Procedure.

2. Technical explanation

NHTSA-hosted Ford TSB 21-2405 states that some 2021 Mustang Mach-E vehicles built on or before September 9, 2021 may have U0100:00 stored in the GSM, along with other listed DTCs. In the bulletin's covered condition, Ford attributes the issue to software in the GSM and specifies reprogramming the GSM to correct it. The supplied evidence does not establish a broader definition of U0100:00 outside this bulletin context.

3. What system is affected?

Gear shift module (GSM).

4. How serious is this code?

Not yet established by verified evidence.

5. Symptoms you may notice

  • An illuminated powertrain malfunction (wrench) indicator may be present.
  • The message “Shift System Fault – Service required” may be displayed.

6. Possible causes

  • For the condition covered by Ford TSB 21-2405, Ford identifies software in the gear shift module (GSM).

7. Can I still drive the vehicle?

Not yet established by verified evidence.

8. Can I charge the vehicle?

Not yet established by verified evidence.

9. What you can safely do

  • Arrange diagnosis by a Ford dealer or qualified service facility if the wrench indicator or “Shift System Fault – Service required” message is present.
  • Provide the stored DTC information and ask whether Ford TSB 21-2405 applies to the vehicle.

10. Step-by-step troubleshooting

  1. Confirm the vehicle is a 2021 Ford Mustang Mach-E.
  2. Confirm the vehicle was built on or before September 9, 2021.
  3. Check whether U0100:00 is stored in the GSM and whether the documented warning indicator or shift-system message is present.
  4. If the bulletin criteria are met, follow Ford TSB 21-2405 Service Procedure for GSM reprogramming.

11. When to contact service

Contact a Ford dealer or qualified service facility to determine whether TSB 21-2405 applies and to perform the specified GSM reprogramming procedure.

12. What the service center may check

  • Verify model year, model, and build-date eligibility: 2021 Mustang Mach-E built on or before September 9, 2021.
  • Check for U0100:00 in the GSM.
  • Check for related stored codes identified in the bulletin.
  • Determine whether the powertrain malfunction indicator and/or “Shift System Fault – Service required” message is present.

13. Possible repair or resolution

  • Ford TSB 21-2405 directs reprogramming of the gear shift module (GSM) for vehicles meeting its criteria.

14. Affected vehicles

15. Related TSBs / service bulletins

  • Ford TSB 21-2405, published November 17, 2021: applies to some 2021 Ford Mustang Mach-E vehicles built on or before September 9, 2021. It documents U0100:00 as a possible GSM code, identifies GSM software as the cause of the covered condition, and directs GSM reprogramming.

16. Recall information

  • Not yet established by verified evidence.

17. Official manufacturer information

Official source: NHTSA Manufacturer Communication PDF 10203653, Ford TSB 21-2405: https://static.nhtsa.gov/odi/tsbs/2021/MC-10203653-0001.pdf

19. Frequently asked questions

Does TSB 21-2405 apply to every Mustang Mach-E?

No. The supplied bulletin applies to certain 2021 Mustang Mach-E vehicles built on or before September 9, 2021.

What repair does Ford specify in TSB 21-2405?

Ford directs technicians to follow the Service Procedure to reprogram the GSM.

Can U0100:00 occur with other codes under this bulletin?

Yes. The bulletin states that U0100:00, U0121, U0140, and/or U0155 may be stored in the GSM; it also describes U0103:87 stored in the SOBDMC.

20. Sources & verification

Verified
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