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Mitsubishi P1B30

ECU. Q: Is the diagnostic trouble code stored? YES : If diagnostic trouble code No. P1B30 is stored in the EV-ECU, replace the BMU. NO : If no diagnostic trouble code No. P1B30 is

DriveNot yet established by verified evidence.
ChargeNot yet established by verified evidence.
ServiceService evaluation is appropriate because the verified Mitsubishi procedure directs BMU replacement when P1B30 is stored in the EV-ECU.
Confidence95%

Quick answer

For verified U.S. 2012 and 2014 Mitsubishi i-MiEV applicability, official Mitsubishi TSB diagnostic instructions state that if P1B30 is stored in the EV-ECU, replace the BMU (Battery Management Unit).

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 P1B30 mean?

For verified U.S. 2012 and 2014 Mitsubishi i-MiEV applicability, official Mitsubishi TSB diagnostic instructions state that if P1B30 is stored in the EV-ECU, replace the BMU (Battery Management Unit).

2. Technical explanation

P1B30 is documented in official Mitsubishi manufacturer communications submitted to NHTSA. In diagnostic Step 3, Mitsubishi instructs use of scan tool MB991958 to check whether P1B30 is stored in the EV-ECU. If it is stored, the instruction is to replace the BMU. If it is not stored, the procedure continues to Step 4, where the technician checks for P1AAB in the BMU using the CMU ID numbering special function. The supplied evidence does not establish a plain-language fault definition for P1B30 beyond this diagnostic decision path.

3. What system is affected?

The verified evidence identifies the EV-ECU as the module in which P1B30 is checked and specifies replacement of the BMU when P1B30 is stored. A more specific affected-system description is not yet established by verified evidence.

4. How serious is this code?

Not yet established by verified evidence.

5. Symptoms you may notice

Not yet established by verified evidence.

6. Possible causes

  • Official Mitsubishi diagnostic instructions treat a stored P1B30 in the EV-ECU as a condition for BMU replacement. The underlying failure mechanism 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

  • Have the vehicle evaluated by a qualified Mitsubishi EV service provider using the specified diagnostic process.
  • Do not attempt high-voltage battery or BMU repair procedures yourself.

10. Step-by-step troubleshooting

  1. A qualified technician uses scan tool MB991958 to check whether P1B30 is stored in the EV-ECU.
  2. If P1B30 is stored in the EV-ECU, the official instruction is to replace the BMU.
  3. If P1B30 is not stored, the official procedure advances to Step 4 and checks whether P1AAB is stored in the BMU using the CMU ID numbering special function.

11. When to contact service

Service evaluation is appropriate because the verified Mitsubishi procedure directs BMU replacement when P1B30 is stored in the EV-ECU.

12. What the service center may check

  • Confirm P1B30 status in the EV-ECU with scan tool MB991958.
  • When P1B30 is not stored, execute the BMU CMU ID numbering special function and check for P1AAB, as directed in the cited procedure.

13. Possible repair or resolution

  • For a stored P1B30 in the EV-ECU, Mitsubishi TSB diagnostic instructions specify replacement of the BMU.
  • Further repair outcomes for the no-P1B30 branch are not fully established by the supplied evidence.

14. Affected vehicles

15. Related TSBs / service bulletins

  • Mitsubishi TSB-19-54-004, published March 13, 2019; NHTSA manufacturer communication MC-10158409. It includes the P1B30 EV-ECU check and directs BMU replacement if the code is stored.
  • Mitsubishi TSB-19-54-003, published March 13, 2019; NHTSA manufacturer communication MC-10158408. It includes the same supplied P1B30 diagnostic decision path.

16. Recall information

No recall relationship is established by verified evidence.

17. Official manufacturer information

Verified official sources: NHTSA-hosted Mitsubishi manufacturer communications MC-10158409 (TSB-19-54-004) and MC-10158408 (TSB-19-54-003), both published March 13, 2019. Verified applicability supplied: U.S.-market 2012 and 2014 Mitsubishi i-MiEV.

19. Frequently asked questions

What does Mitsubishi instruct when P1B30 is stored in the EV-ECU?

Replace the BMU, according to the cited Mitsubishi TSB diagnostic procedure.

What happens if P1B30 is not stored?

The procedure proceeds to Step 4, which checks for P1AAB in the BMU using the CMU ID numbering special function.

Can I safely drive or charge with P1B30?

Not yet established by verified evidence.

20. Sources & verification

Verified
Mitsubishi P1B30: ECU. Q: Is the diagnostic trouble code stored? YES :… | EV Diagnostics