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Mitsubishi P1AC1

ion batt ery is charged. Judgment Criterion  For more than 5 seconds, the PWM output signal of the main drive lithium-ion ba ttery fan is 10 percent (while the fan is being driven

DriveNot yet established by verified evidence.
ChargeNot yet established by verified evidence.
ServiceService is recommended because P1AC1 concerns the main drive lithium-ion battery cooling fan system. Driveability and charging suitability are not established by the supplied verified evidence.
Confidence95%

Quick answer

P1AC1 is a Mitsubishi i-MiEV battery cooling fan drive-fail DTC. Verified evidence applies to the 2016 US i-MiEV and identifies the main drive lithium-ion battery fan PWM/rotation feedback as the diagnostic focus.

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 P1AC1 mean?

P1AC1 is a Mitsubishi i-MiEV battery cooling fan drive-fail DTC. Verified evidence applies to the 2016 US i-MiEV and identifies the main drive lithium-ion battery fan PWM/rotation feedback as the diagnostic focus.

2. Technical explanation

The official Mitsubishi TSB identifies P1AC1 as “Battery Cooling Fan (Drive Fail).” It can be judged with the electric motor switch ON or while the main drive lithium-ion battery is charging. The stated judgment criterion is that, for more than 5 seconds while the fan is driven, the fan PWM output signal is 10 percent and the fan rotation-related output condition is detected as abnormal. The supplied evidence excerpt is truncated, so the complete judgment wording is not established by verified evidence.

3. What system is affected?

Main drive lithium-ion battery cooling fan system.

4. How serious is this code?

Not yet established by verified evidence.

5. Symptoms you may notice

  • A stored P1AC1 diagnostic trouble code.
  • Additional driver-visible symptoms are not yet established by verified evidence.

6. Possible causes

  • A fault condition involving the main drive lithium-ion battery cooling fan drive/feedback circuit is indicated by the DTC definition.
  • Specific failed parts or wiring causes are 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-qualified EV service facility.
  • Do not perform high-voltage battery disassembly or repair based on this code.

10. Step-by-step troubleshooting

  1. Use the official Mitsubishi diagnostic procedure for P1AC1.
  2. The verified TSB directs diagnosis toward the main drive lithium-ion battery fan PWM output and rotation-related signal while the fan is commanded to operate.
  3. If an intermittent malfunction is indicated by the applicable diagnostic checks, the TSB refers technicians to Mitsubishi intermittent-malfunction troubleshooting guidance.

11. When to contact service

Service is recommended because P1AC1 concerns the main drive lithium-ion battery cooling fan system. Driveability and charging suitability are not established by the supplied verified evidence.

12. What the service center may check

  • Confirm P1AC1 and follow the Mitsubishi DTC P1AC1 troubleshooting procedure.
  • Evaluate the battery cooling fan command/output and rotation-related feedback condition under the stated check conditions.
  • Apply the official intermittent-malfunction process if the relevant check result is normal.

13. Possible repair or resolution

  • Not yet established by verified evidence. The supplied excerpt identifies the diagnostic area but does not provide a verified P1AC1 repair outcome.

14. Affected vehicles

15. Related TSBs / service bulletins

  • Mitsubishi TSB-19-54-005, published March 13, 2019; NHTSA Manufacturer Communication PDF 10158410. The supplied evidence includes the P1AC1 Battery Cooling Fan (Drive Fail) diagnostic section.

16. Recall information

  • No recall information is established by the supplied verified evidence.

17. Official manufacturer information

Official source: NHTSA-hosted Mitsubishi manufacturer communication, TSB-19-54-005: https://static.nhtsa.gov/odi/tsbs/2019/MC-10158410-9999.pdf

19. Frequently asked questions

What does Mitsubishi P1AC1 mean?

The verified Mitsubishi TSB identifies P1AC1 as Battery Cooling Fan (Drive Fail).

Which vehicle is covered by the supplied evidence?

The verified applicability record covers the 2016 Mitsubishi i-MiEV in the United States.

Can I drive or charge with P1AC1?

Not yet established by verified evidence.

20. Sources & verification

Verified
Mitsubishi P1AC1: ion batt ery is charged. Judgment Criterion  For… | EV Diagnostics