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Mitsubishi P1A40

Main Drive Lithium-ion Battery current sensor (high) a bnormal c. P1A41: Main Drive Lithium-ion Battery current sensor (low) abnormal J udgment Criterion  The output voltage of th

DriveNot yet established by verified evidence.
ChargeNot yet established by verified evidence.
ServiceContact a qualified Mitsubishi EV service provider for diagnosis. The supplied evidence does not establish whether immediate service is required.
Confidence95%

Quick answer

P1A40 is documented for certain U.S.-market Mitsubishi i-MiEV model years as a Main Drive Lithium-ion Battery current sensor (high) abnormal code. Verified bulletin evidence identifies an abnormal high-current-sensor output-voltage condition.

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 P1A40 mean?

P1A40 is documented for certain U.S.-market Mitsubishi i-MiEV model years as a Main Drive Lithium-ion Battery current sensor (high) abnormal code. Verified bulletin evidence identifies an abnormal high-current-sensor output-voltage condition.

2. Technical explanation

The supplied official Mitsubishi/NHTSA bulletin evidence states that P1A40 concerns the Main Drive Lithium-ion Battery current sensor (high). The judgment criterion cited in the evidence is that the high sensor output voltage is less than 0.3 V or more than 4.7 V. The evidence describes monitoring with the electric motor switch ON or while the main drive lithium-ion battery starts charging; another supplied bulletin excerpt states a check condition of three seconds after switch-on or three seconds after charging starts. The supplied evidence does not establish a complete diagnostic procedure or a specific component-level repair.

3. What system is affected?

Main Drive Lithium-ion Battery current sensor (high), as named in the verified Mitsubishi bulletin evidence.

4. How serious is this code?

Not yet established by verified evidence.

5. Symptoms you may notice

  • A P1A40 diagnostic trouble code may be stored under the documented monitoring conditions. No driver-observable symptoms are established by the supplied verified evidence.

6. Possible causes

  • The verified judgment criterion is an output voltage from the Main Drive Lithium-ion Battery current sensor (high) below 0.3 V or above 4.7 V.
  • Specific underlying 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

  • Do not attempt high-voltage battery or current-sensor repairs yourself.
  • Arrange diagnosis by a qualified Mitsubishi EV service provider using the applicable manufacturer information.

10. Step-by-step troubleshooting

  1. A qualified technician can confirm whether P1A40 is stored and evaluate it using the applicable Mitsubishi service information.
  2. The supplied evidence identifies monitoring with the electric motor switch ON or while the main drive lithium-ion battery begins charging.
  3. The supplied evidence identifies the high current-sensor output-voltage limits as below 0.3 V or above 4.7 V.

11. When to contact service

Contact a qualified Mitsubishi EV service provider for diagnosis. The supplied evidence does not establish whether immediate service is required.

12. What the service center may check

  • Confirm P1A40 using appropriate diagnostic equipment.
  • Evaluate the Main Drive Lithium-ion Battery current sensor (high) output against the documented threshold: less than 0.3 V or more than 4.7 V.
  • Use the applicable manufacturer service information; further service checks are not established by the supplied evidence.

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 March 13, 2019; available through NHTSA Manufacturer Communication PDF 10158408: https://static.nhtsa.gov/odi/tsbs/2019/MC-10158408-9999.pdf
  • Mitsubishi TSB-19-54-004, published March 13, 2019; available through NHTSA Manufacturer Communication PDF 10158409: https://static.nhtsa.gov/odi/tsbs/2019/MC-10158409-9999.pdf
  • Mitsubishi TSB-19-54-005, published March 13, 2019; available through NHTSA Manufacturer Communication PDF 10158410: https://static.nhtsa.gov/odi/tsbs/2019/MC-10158410-9999.pdf

16. Recall information

  • Not yet established by verified evidence.

17. Official manufacturer information

Verified source: NHTSA-hosted Mitsubishi manufacturer communications, including TSB-19-54-003, TSB-19-54-004, and TSB-19-54-005, published March 13, 2019.

19. Frequently asked questions

What does P1A40 mean?

For the supported Mitsubishi i-MiEV applications, P1A40 is identified as Main Drive Lithium-ion Battery current sensor (high) abnormal.

What measurement triggers P1A40?

The supplied official bulletin evidence states that the high current-sensor output voltage is less than 0.3 V or more than 4.7 V.

When is the condition checked?

The evidence describes checks with the electric motor switch ON or while the main drive lithium-ion battery starts charging. One supplied bulletin excerpt also specifies three seconds after switch-on or three seconds after charging starts.

Can the vehicle be driven or charged with P1A40?

Not yet established by verified evidence.

Which vehicles are supported by the supplied evidence?

U.S.-market Mitsubishi i-MiEV model years 2012, 2014, and 2016.

20. Sources & verification

Verified
Mitsubishi P1A40: Main Drive Lithium-ion Battery current sensor (high)… | EV Diagnostics