Ford U101E
Proceed to step 25. No – Proceed to step 28. 25. From the list on the LH side of the screen, select the SOBDMC. 26. From the list on the RH side of the screen, select SOBDMC - Rese
Quick answer
For a 2021 Ford Mustang Mach-E in the US, U101E appears in Ford/NHTSA communication 21P22-S1 as a DTC assessed together with P1A10 after clearing and retesting DTCs. The supplied evidence does not establish a plain-language fault definition for U101E.
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 U101E mean?
For a 2021 Ford Mustang Mach-E in the US, U101E appears in Ford/NHTSA communication 21P22-S1 as a DTC assessed together with P1A10 after clearing and retesting DTCs. The supplied evidence does not establish a plain-language fault definition for U101E.
2. Technical explanation
The verified procedure instructs a technician to run a self-test, clear DTCs in all modules, then determine whether P1A10 and U101E remain present. If both remain, the procedure directs selection of the Secondary On-Board Diagnostic Control Module C (SOBDMC) and execution of an SOBDMC reset using the service tool, following on-screen instructions. If they do not remain, the procedure directs the technician to proceed to a later step not included in the supplied evidence.
3. What system is affected?
The verified evidence names the Secondary On-Board Diagnostic Control Module C (SOBDMC). A broader vehicle system assignment is not yet established by verified evidence.
4. How serious is this code?
Unknown. The supplied evidence does not assign a severity level.
5. Symptoms you may notice
- Not yet established by verified evidence.
6. Possible causes
- Not yet established by verified evidence.
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 EV service facility if U101E is present.
- Do not attempt module reset, diagnostic-tool operations, or high-voltage repairs without appropriate training and equipment.
10. Step-by-step troubleshooting
- Verified service procedure: run the listed self-test using the service tool.
- Clear DTCs in all modules and retest.
- Determine whether P1A10 and U101E are still present.
- If P1A10 and U101E remain present, select SOBDMC and run “SOBDMC - Reset the Secondary On-Board Diagnostic Control Module C (SOBDMC),” following all on-screen instructions carefully.
11. When to contact service
Service is appropriate because the verified procedure requires manufacturer diagnostic-tool functions and an SOBDMC reset when P1A10 and U101E remain after clearing and retesting.
12. What the service center may check
- Run the applicable self-test.
- Clear and retest DTCs in all modules.
- Confirm whether P1A10 and U101E remain present.
- If present, perform the specified SOBDMC reset through the service tool.
13. Possible repair or resolution
- The supplied evidence identifies an SOBDMC reset as the next verified action when P1A10 and U101E remain after clearing and retesting.
- Whether this resolves the condition is not yet established by verified evidence.
14. Affected vehicles
- Ford Mustang Mach-E · 2021 · US
15. Related TSBs / service bulletins
- NHTSA Manufacturer Communication PDF 10209373: Ford communication 21P22-S1, published March 28, 2022. It includes the verified diagnostic sequence for P1A10 and U101E, including the SOBDMC reset instruction.
16. Recall information
- Not yet established by verified evidence.
17. Official manufacturer information
Official source: NHTSA Manufacturer Communication PDF 10209373 (Ford 21P22-S1), published 2022-03-28: https://static.nhtsa.gov/odi/tsbs/2022/MC-10209373-0001.pdf
19. Frequently asked questions
What does U101E mean on a 2021 Ford Mustang Mach-E?
The supplied verified evidence does not provide a plain-language definition. It documents U101E as a DTC evaluated with P1A10 in Ford communication 21P22-S1.
What does Ford's documented procedure do if U101E remains after clearing codes?
If P1A10 and U101E remain after clearing and retesting, the procedure directs a technician to run an SOBDMC reset with the service tool and follow on-screen instructions.
Is U101E confirmed to be safe to drive or charge with?
Not yet established by verified evidence.