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Mitsubishi U11AA

CMU11 time-out, U11AB: CMU12 time-out . M S B - 1 7 M 5 4 _ 5 5 - 0 0 1 ( 1 7 A B 0 3 7 ) 1 6 1 BATTERY MANAGEMENT UNIT (BMU) AND MAIN DRIVE LITHIUM-ION BATTERY TSB Revision ELECTR

DriveNot yet established by verified evidence.
ChargeNot yet established by verified evidence.
ServiceProfessional diagnosis is appropriate because this code is documented within the BMU and main drive lithium-ion battery service material. Service urgency is not yet established by verified evidence.
Confidence95%

Quick answer

U11AA is a Mitsubishi i-MiEV diagnostic trouble code for a CMU11 time-out (also described as CMU11 CAN timeout). Verified evidence places it in the Battery Management Unit (BMU) and main drive lithium-ion battery diagnostic material.

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 U11AA mean?

U11AA is a Mitsubishi i-MiEV diagnostic trouble code for a CMU11 time-out (also described as CMU11 CAN timeout). Verified evidence places it in the Battery Management Unit (BMU) and main drive lithium-ion battery diagnostic material.

2. Technical explanation

The official Mitsubishi service material identifies U11AA as “CMU11 time-out” / “CMU11 CAN Timeout.” The listed judgment conditions include three seconds after the electric motor switch is turned ON, or three seconds after main drive lithium-ion battery charging begins. One cited procedure also states that U1082, for the local CAN bus of the main drive lithium-ion battery, must not be stored for this judgment condition. The supplied evidence does not establish a specific failed part or a complete root-cause list for U11AA.

3. What system is affected?

Battery Management Unit (BMU) and main drive lithium-ion battery; specifically the CMU11 communication/time-out diagnostic path.

4. How serious is this code?

Not yet established by verified evidence.

5. Symptoms you may notice

  • A U11AA diagnostic trouble code may be stored.
  • No driver-visible symptoms are established by the supplied verified evidence.

6. Possible causes

  • A CMU11 communication time-out / CAN timeout condition is established by verified evidence.
  • A specific underlying cause is 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 Mitsubishi dealer or qualified EV service provider.
  • Do not attempt high-voltage battery, Battery Management Unit, CMU, or battery communication-system repairs yourself.

10. Step-by-step troubleshooting

  1. Use the applicable Mitsubishi diagnostic procedure to confirm whether U11AA is stored or set.
  2. The official material evaluates the code after three seconds with the electric motor switch ON or after three seconds of main drive battery charging.
  3. Check whether U1082 is stored where the applicable official procedure requires that code to be absent for U11AA judgment.
  4. Further diagnostic steps and repair decisions should follow the applicable Mitsubishi service information.

11. When to contact service

Professional diagnosis is appropriate because this code is documented within the BMU and main drive lithium-ion battery service material. Service urgency is not yet established by verified evidence.

12. What the service center may check

  • Confirm U11AA with the applicable diagnostic tool and procedure.
  • Apply the official timing conditions: three seconds after electric motor switch ON or three seconds after charging starts.
  • Review U1082 status when using the procedure that specifies U1082 must not be stored.
  • Follow the applicable Mitsubishi BMU and main drive lithium-ion battery diagnostic flow.

13. Possible repair or resolution

  • Not yet established by verified evidence.

14. Affected vehicles

15. Related TSBs / service bulletins

  • Mitsubishi TSB-19-54-003, published through NHTSA as manufacturer communication MC-10158408 on 2019-03-13. It identifies U11AA as CMU11 time-out.
  • Mitsubishi TSB-19-54-004, published through NHTSA as manufacturer communication MC-10158409 on 2019-03-13. It identifies U11AA as CMU11 time-out and includes the cited judgment conditions.
  • Mitsubishi TSB-19-54-005, published through NHTSA as manufacturer communication MC-10158410 on 2019-03-13. It identifies U11AA as CMU11 CAN Timeout.

16. Recall information

  • Not yet established by verified evidence.

17. Official manufacturer information

Verified official sources: NHTSA-hosted Mitsubishi manufacturer communications MC-10158408, MC-10158409, and MC-10158410, published 2019-03-13. https://static.nhtsa.gov/odi/tsbs/2019/MC-10158408-9999.pdf ; https://static.nhtsa.gov/odi/tsbs/2019/MC-10158409-9999.pdf ; https://static.nhtsa.gov/odi/tsbs/2019/MC-10158410-9999.pdf

19. Frequently asked questions

What does U11AA mean on a Mitsubishi i-MiEV?

It means CMU11 time-out, also described in official material as CMU11 CAN Timeout.

Which vehicles are established as applicable?

The supplied verified applicability data identifies U.S.-market Mitsubishi i-MiEV model years 2012, 2014, and 2016.

Can I continue driving or charging?

Not yet established by verified evidence.

Does U11AA identify a specific failed component?

No specific failed component is established by the supplied verified evidence.

20. Sources & verification

Verified
Mitsubishi U11AA: CMU11 time-out, U11AB: CMU12 time-out . M S B - 1 7… | EV Diagnostics