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Mitsubishi P1AB5

CMU01 module temperature abnormal (low input), P1AB6: CMU02 module temperature abnormal (low input), P1AB7: CMU03 module temperature abnormal (low input), P1AB8: CMU04 module tempe

DriveNot yet established by verified evidence.
ChargeNot yet established by verified evidence.
ServiceService evaluation is appropriate because the documented diagnostic procedure involves the BMU and may direct replacement of the Main Drive Lithium-ion Battery. Driving and charging suitability are not established by the supplied evidence.
Confidence95%

Quick answer

P1AB5 is identified in Mitsubishi service bulletin evidence as “CMU01 module temperature abnormal (low input).” It applies to the 2012 and 2014 Mitsubishi i-MiEV in the US based on the supplied verified applicability data.

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 P1AB5 mean?

P1AB5 is identified in Mitsubishi service bulletin evidence as “CMU01 module temperature abnormal (low input).” It applies to the 2012 and 2014 Mitsubishi i-MiEV in the US based on the supplied verified applicability data.

2. Technical explanation

The supplied NHTSA-hosted Mitsubishi TSB evidence identifies P1AB5 as a battery-monitoring-related diagnostic code for CMU01 module temperature abnormal (low input). The same bulletin evidence lists related CMU temperature-low-input codes for other CMUs. Mitsubishi’s documented diagnostic path includes checking whether DTC P1AAB is stored in the BMU after executing the BMU “CMU ID numbering” special function. The bulletin states: if P1AAB is stored, replace the Main Drive Lithium-ion Battery; if it is not stored, the diagnosis is complete. The evidence does not establish an underlying component-level cause beyond this diagnostic procedure.

3. What system is affected?

The verified evidence refers to CMU01 and the BMU, and its prescribed repair—when the documented condition is met—is replacement of the Main Drive Lithium-ion Battery.

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 evidence identifies P1AB5 as “CMU01 module temperature abnormal (low input).”
  • A more specific root 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

  • Do not attempt high-voltage battery diagnosis, disassembly, or repair yourself.
  • Have a Mitsubishi-qualified service facility diagnose the vehicle using the documented BMU procedure.

10. Step-by-step troubleshooting

  1. Mitsubishi’s TSB evidence directs a technician to execute “CMU ID numbering” from the BMU special-function screen.
  2. The technician then checks whether DTC P1AAB is stored in the BMU.
  3. If P1AAB is stored, the bulletin directs replacement of the Main Drive Lithium-ion Battery.
  4. If P1AAB is not stored, the bulletin states that diagnosis is complete.

11. When to contact service

Service evaluation is appropriate because the documented diagnostic procedure involves the BMU and may direct replacement of the Main Drive Lithium-ion Battery. Driving and charging suitability are not established by the supplied evidence.

12. What the service center may check

  • Read BMU diagnostic trouble codes.
  • Execute the BMU “CMU ID numbering” special function.
  • Check whether P1AAB is stored in the BMU.

13. Possible repair or resolution

  • Per the cited Mitsubishi TSB procedure, replace the Main Drive Lithium-ion Battery if P1AAB is stored after the specified BMU procedure.
  • If P1AAB is not stored, the cited procedure states that diagnosis is complete.

14. Affected vehicles

15. Related TSBs / service bulletins

  • Mitsubishi TSB-19-54-004, published March 13, 2019; NHTSA manufacturer communication MC-10158409: https://static.nhtsa.gov/odi/tsbs/2019/MC-10158409-9999.pdf
  • Mitsubishi TSB-19-54-003, published March 13, 2019; NHTSA manufacturer communication MC-10158408: https://static.nhtsa.gov/odi/tsbs/2019/MC-10158408-9999.pdf

16. Recall information

  • Not yet established by verified evidence.

17. Official manufacturer information

Verified official evidence is available in NHTSA-hosted Mitsubishi manufacturer communications TSB-19-54-004 and TSB-19-54-003. The supplied applicability data covers US-market 2012 and 2014 Mitsubishi i-MiEV vehicles.

19. Frequently asked questions

What does P1AB5 mean?

The verified Mitsubishi TSB evidence defines P1AB5 as “CMU01 module temperature abnormal (low input).”

Which vehicles are covered by the supplied applicability data?

US-market Mitsubishi i-MiEV vehicles for model years 2012 and 2014.

What repair does the Mitsubishi procedure specify?

After the documented BMU CMU ID numbering procedure, Mitsubishi directs replacement of the Main Drive Lithium-ion Battery if P1AAB is stored. If P1AAB is not stored, the bulletin says diagnosis is complete.

Is it safe to drive or charge with P1AB5?

Not yet established by verified evidence.

20. Sources & verification

Verified
Mitsubishi P1AB5: CMU01 module temperature abnormal (low input),… | EV Diagnostics