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Mitsubishi P1AC6

ion battery starts to be charged.  The absolute value of the current is less than 1 ampere.  The battery total voltage is more than 350 volts.  Either one of the fo

DriveNot yet established by verified evidence.
ChargeNot yet established by verified evidence.
ServiceContact a Mitsubishi dealer or qualified EV service facility for diagnosis, particularly because the bulletin procedure concerns the main drive lithium-ion battery and its cooling fan.
Confidence95%

Quick answer

P1AC6 is documented for certain U.S. Mitsubishi i-MiEV vehicles as “Each Cell VOLT. Diff. (HI Side).” A Mitsubishi bulletin includes a diagnostic path that calls for scan-tool confirmation; if the DTC is set, it directs replacement of the cooling fan in the main drive lithium-ion battery.

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 P1AC6 mean?

P1AC6 is documented for certain U.S. Mitsubishi i-MiEV vehicles as “Each Cell VOLT. Diff. (HI Side).” A Mitsubishi bulletin includes a diagnostic path that calls for scan-tool confirmation; if the DTC is set, it directs replacement of the cooling fan in the main drive lithium-ion battery.

2. Technical explanation

Verified Mitsubishi service information identifies P1AC6 as “Each Cell VOLT. Diff. (HI Side).” The listed judgment conditions include: at least 3 seconds after the electric motor switch is turned ON or after main drive lithium-ion battery charging begins; absolute current below 1 ampere; battery total voltage above 350 volts; and one of additional conditions that is truncated in the supplied evidence. The complete fault criteria are therefore not yet established by verified evidence.

3. What system is affected?

Main drive lithium-ion battery; the verified TSB diagnostic procedure also references its cooling fan.

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

  • The verified Mitsubishi bulletin provides a repair direction involving the cooling fan in the main drive lithium-ion battery when P1AC6 is confirmed. The underlying failure mechanism is not otherwise established by the supplied verified evidence.
  • The bulletin also identifies an intermittent malfunction path when the DTC is not set.

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-capable service facility using the specified scan-tool procedure.
  • Do not attempt high-voltage battery or battery cooling-fan repair yourself.

10. Step-by-step troubleshooting

  1. Use scan tool MB991958 to confirm whether the DTC is set, as specified in Mitsubishi TSB-19-54-005.
  2. If P1AC6 is not set during the bulletin procedure, Mitsubishi identifies the condition as an intermittent malfunction and refers technicians to its intermittent-malfunction diagnostic process.

11. When to contact service

Contact a Mitsubishi dealer or qualified EV service facility for diagnosis, particularly because the bulletin procedure concerns the main drive lithium-ion battery and its cooling fan.

12. What the service center may check

  • Confirm P1AC6 with scan tool MB991958.
  • If confirmed, follow the Mitsubishi bulletin diagnostic path for the main drive lithium-ion battery cooling fan.
  • If not confirmed, follow Mitsubishi intermittent-malfunction diagnostic guidance.

13. Possible repair or resolution

  • Mitsubishi TSB-19-54-005 directs replacement of the cooling fan in the main drive lithium-ion battery when the diagnostic trouble code is confirmed in its stated procedure.
  • If the DTC is not set, the bulletin directs technicians to address the condition as an intermittent malfunction rather than replacing the fan under that decision point.

14. Affected vehicles

15. Related TSBs / service bulletins

  • TSB-19-54-005, published March 13, 2019: Includes P1AC6 diagnostic information, scan-tool confirmation using MB991958, and a decision path directing main drive lithium-ion battery cooling-fan replacement when the DTC is set.
  • TSB1754003, published July 26, 2017: Supersedes TSB-15-54-002, adds P1AC6 as a possible trouble code, updates parts information, and updates MUT3-SE screenshots.

16. Recall information

No recall relationship is established by verified evidence.

17. Official manufacturer information

Verified official-source evidence is from NHTSA-hosted Mitsubishi manufacturer communications: TSB-19-54-005 (NHTSA MC-10158410-9999) and TSB1754003 (NHTSA manufacturer communications 10115257 and 10116253).

19. Frequently asked questions

What does Mitsubishi P1AC6 mean?

The verified Mitsubishi bulletin labels P1AC6 “Each Cell VOLT. Diff. (HI Side).”

Which vehicles are established by the supplied evidence?

The supplied applicability data identifies U.S.-market Mitsubishi i-MiEV model years 2012–2013 and 2016.

What repair does Mitsubishi specify if P1AC6 is confirmed?

In TSB-19-54-005, Mitsubishi directs replacement of the cooling fan in the main drive lithium-ion battery after scan-tool confirmation that the DTC is set.

Is P1AC6 safe to drive or charge with?

Not yet established by verified evidence.

20. Sources & verification

Verified
Mitsubishi P1AC6: ion battery starts to be charged.  The absolute… | EV Diagnostics