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Tesla UI_a004

Front trunk open Proceed with caution

Common search variants: UIa004 · UI-a004 · UI a004 · Search ignores case and common separators.

DriveUnknown in the diagnostic record. Verified documentation says “Proceed with caution,” but does not establish a general determination that the vehicle is safe to drive with this alert active.
ChargeNot yet established by verified evidence.
ServiceNot yet established by verified evidence whether service is required for every occurrence. Contact Tesla service if the front trunk cannot be confirmed fully secured or the alert persists.
Confidence95%

Quick answer

UI_a004 means the vehicle detected that the front trunk (hood) is open while driving, or that it cannot confirm the front trunk primary and/or secondary latch is fully secured.

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 UI_a004 mean?

UI_a004 means the vehicle detected that the front trunk (hood) is open while driving, or that it cannot confirm the front trunk primary and/or secondary latch is fully secured.

2. Technical explanation

Tesla documentation submitted to NHTSA states that this alert occurs when the front trunk (hood) is detected open while driving. It indicates that at least one of the two hood-retention latches—the front trunk primary latch and/or secondary latch—cannot be confirmed closed when the vehicle is shifted into a drive gear.

3. What system is affected?

Front trunk (hood) closure and latching system, including the primary and secondary latches.

4. How serious is this code?

The diagnostic record lists severity as unknown. The alert instructs: “Proceed with caution.”

5. Symptoms you may notice

  • The UI_a004 alert: “Front trunk open Proceed with caution.”
  • The vehicle detects the front trunk/hood as open while driving or cannot confirm one or both hood latches are fully secured.

6. Possible causes

  • The front trunk (hood) is open while driving.
  • At least one of the front trunk primary or secondary latches cannot be confirmed fully closed and secured.
  • Further underlying causes are not yet established by verified evidence.

7. Can I still drive the vehicle?

Unknown in the diagnostic record. Verified documentation says “Proceed with caution,” but does not establish a general determination that the vehicle is safe to drive with this alert active.

8. Can I charge the vehicle?

Not yet established by verified evidence.

9. What you can safely do

  • Proceed with caution, consistent with the alert message.
  • Do not rely on the alert clearing alone as confirmation that both hood latches are fully secured.
  • Use Tesla service if the alert remains active or if the hood cannot be confirmed fully secured. Detailed owner actions are not established by the supplied verified evidence.

10. Step-by-step troubleshooting

  1. The verified evidence establishes that the alert concerns confirmation of the front trunk primary and/or secondary latch closure.
  2. Specific owner troubleshooting steps are not yet established by verified evidence.

11. When to contact service

Not yet established by verified evidence whether service is required for every occurrence. Contact Tesla service if the front trunk cannot be confirmed fully secured or the alert persists.

12. What the service center may check

  • Confirm the condition of the front trunk closure and the ability of the primary and secondary latches to be confirmed fully closed. Additional service procedures are not yet established by verified evidence.

13. Possible repair or resolution

  • Not yet established by verified evidence.

14. Affected vehicles

15. Related TSBs / service bulletins

  • Official NHTSA manufacturer communications contain Tesla owner-manual material describing UI_a004, including NHTSA Manufacturer Communication PDFs 10253666, 10253669, 10253661, 10250484, 10240947, and 10240949. The supplied evidence does not establish a repair bulletin or a prescribed repair for this alert.

16. Recall information

  • Not yet established by verified evidence.

17. Official manufacturer information

Official NHTSA-hosted Tesla manufacturer communications describe UI_a004 as a front trunk/hood open or unconfirmed-latch condition. Example: https://static.nhtsa.gov/odi/tsbs/2024/MC-10253666-9999.pdf

19. Frequently asked questions

What does Tesla alert UI_a004 mean?

It means the vehicle detected the front trunk (hood) open while driving, or cannot confirm that the primary and/or secondary hood latch is fully secured.

Which latches are involved?

Tesla documentation identifies the front trunk primary latch and secondary latch.

Is it safe to drive with UI_a004?

The diagnostic record marks drive safety as unknown. The verified alert text says “Proceed with caution,” but does not establish a general safe-to-drive determination.

Can I charge with UI_a004 active?

Not yet established by verified evidence.

Does UI_a004 identify a specific failed part?

No. The supplied evidence only establishes that at least one hood latch cannot be confirmed fully closed; it does not identify a specific failed component.

20. Sources & verification

Accepted ResearchVerified
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Tesla UI_a004: Front trunk open Proceed with caution | EV Diagnostics