Mitsubishi P1A81
CMU12 battery cell voltage sensor abnormal . TROUBLE JUDGMENT Check Conditions Three seconds elapse after the electric motor switch is turned ON, or three seconds elapse after th
Quick answer
P1A81 is a Mitsubishi i-MiEV DTC for “CMU12 battery cell voltage sensor abnormal.” Verified applicability is U.S. 2012, 2014, and 2016 i-MiEV models.
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 P1A81 mean?
P1A81 is a Mitsubishi i-MiEV DTC for “CMU12 battery cell voltage sensor abnormal.” Verified applicability is U.S. 2012, 2014, and 2016 i-MiEV models.
2. Technical explanation
Official Mitsubishi service-bulletin evidence identifies P1A81 as an abnormal condition involving the CMU12 battery cell voltage sensor. The judgment conditions include three seconds after the electric motor switch is turned ON or three seconds after main drive lithium-ion battery charging begins. The evidence also states that P1AA8 or U1082 must not be stored/set for this judgment.
3. What system is affected?
Main drive lithium-ion battery monitoring; specifically, the CMU12 battery cell voltage sensor.
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
- An abnormal condition involving the CMU12 battery cell voltage sensor is established by verified evidence. The underlying cause is not yet established by the supplied 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 qualified Mitsubishi EV service provider.
- Do not attempt high-voltage battery, cell-monitoring-unit, or battery-sensor repairs yourself.
10. Step-by-step troubleshooting
- Use suitable diagnostic equipment to confirm P1A81 and check whether P1AA8 or U1082 is also stored, because the official judgment conditions reference those codes.
- Have a qualified technician follow the applicable Mitsubishi service information for the vehicle.
11. When to contact service
Contact a qualified Mitsubishi EV service provider for diagnosis of the main drive lithium-ion battery monitoring system.
12. What the service center may check
- Confirm whether P1A81 is present.
- Check whether P1AA8 (Bat-CAN signal time out / Local CAN for Main Drive Lithium-ion Battery, wording varies among supplied bulletin summaries) is stored.
- Check whether U1082 (Bat-CAN bus-off) is stored.
- Evaluate the CMU12 battery cell voltage sensor condition using applicable Mitsubishi service procedures.
13. Possible repair or resolution
- Not yet established by verified evidence.
14. Affected vehicles
- Mitsubishi i-MiEV · 2012 · US
- Mitsubishi i-MiEV · 2014 · US
- Mitsubishi i-MiEV · 2016 · US
15. Related TSBs / service bulletins
- Mitsubishi TSB-19-54-003, published March 13, 2019; NHTSA manufacturer communication MC-10158408.
- Mitsubishi TSB-19-54-004, published March 13, 2019; NHTSA manufacturer communication MC-10158409.
- Mitsubishi TSB-19-54-005, published March 13, 2019; NHTSA manufacturer communication MC-10158410.
16. Recall information
No recall relationship is established by verified evidence.
17. Official manufacturer information
Official NHTSA-hosted Mitsubishi communications: https://static.nhtsa.gov/odi/tsbs/2019/MC-10158408-9999.pdf ; https://static.nhtsa.gov/odi/tsbs/2019/MC-10158409-9999.pdf ; https://static.nhtsa.gov/odi/tsbs/2019/MC-10158410-9999.pdf
19. Frequently asked questions
What does P1A81 mean?
It means “CMU12 battery cell voltage sensor abnormal” on the verified Mitsubishi i-MiEV applications.
When can P1A81 be judged?
The supplied official bulletin evidence states that judgment may occur three seconds after the electric motor switch is turned ON or three seconds after main drive lithium-ion battery charging starts, provided P1AA8 or U1082 is not stored/set.
Which vehicles are verified as applicable?
U.S. Mitsubishi i-MiEV model years 2012, 2014, and 2016 are established by the supplied evidence.
Can I drive or charge with P1A81?
Not yet established by verified evidence.