Mitsubishi P1A22
ECU. Q: Is the DTC stored? YES : Carry out troubleshooting for the EV-ECU. Then go to Ste p 2. NO : Go to Step 2. STEP 2. Use scan tool MB991958, check freeze frame (FFD) data Chec
Quick answer
P1A22 is documented in Mitsubishi service information as an EV-system diagnostic procedure. Verified evidence supports scan-tool diagnosis, including checking for other EV-ECU DTCs and reviewing freeze-frame data with Mitsubishi scan tool MB991958. The specific fault definition is not yet established by verified evidence.
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 P1A22 mean?
P1A22 is documented in Mitsubishi service information as an EV-system diagnostic procedure. Verified evidence supports scan-tool diagnosis, including checking for other EV-ECU DTCs and reviewing freeze-frame data with Mitsubishi scan tool MB991958. The specific fault definition is not yet established by verified evidence.
2. Technical explanation
For applicable Mitsubishi i-MiEV vehicles, the published diagnostic flow first checks whether DTCs other than P1A22 are stored in the EV-ECU. If other DTCs are stored, the bulletin directs technicians to troubleshoot the EV-ECU and then continue. The next documented step is to review freeze-frame data, including Item No. 33, condenser voltage. The supplied evidence states that the diagnostic material compares condenser voltage with total battery voltage, but the complete acceptance criterion is not available in the verified excerpt.
3. What system is affected?
EV-ECU and related high-voltage EV-system diagnosis. The exact failed component or subsystem for P1A22 is not yet established by verified evidence.
4. How serious is this code?
Unknown. Verified evidence does not provide a severity classification.
5. Symptoms you may notice
- Not yet established by verified evidence.
6. Possible causes
- The cited Mitsubishi diagnostic material references main drive lithium-ion battery bus-bar looseness.
- The cited material references BMU malfunction.
- The cited material references an open circuit in the high-voltage circuit or connection looseness.
- The cited material references EV-ECU malfunction.
- The cited material references EMCU malfunction.
- The evidence excerpt does not establish which of these conditions is the cause in any individual vehicle.
7. Can I still drive the vehicle?
Unknown. Verified evidence does not state whether the vehicle can be driven with P1A22.
8. Can I charge the vehicle?
Unknown. Verified evidence does not state whether the vehicle can be charged with P1A22.
9. What you can safely do
- Have the vehicle evaluated by a Mitsubishi-qualified EV technician using the specified diagnostic process.
- Do not attempt high-voltage battery, bus-bar, or high-voltage-circuit inspection or repair yourself.
- Record any additional stored EV-ECU DTCs and freeze-frame data for the servicing technician.
10. Step-by-step troubleshooting
- Use scan tool MB991958 to check whether DTCs other than P1A22 are stored in the EV-ECU.
- If other EV-ECU DTCs are stored, the documented procedure directs troubleshooting of the EV-ECU before proceeding.
- Review freeze-frame data using scan tool MB991958.
- The documented freeze-frame review includes Item No. 33: condenser voltage.
- Further diagnostic thresholds and repair steps are not yet established by the supplied verified evidence.
11. When to contact service
Service is appropriate because the verified diagnostic process requires Mitsubishi scan tool MB991958 and involves EV high-voltage-system diagnostic references. Driving and charging status are not established by the evidence.
12. What the service center may check
- Check the EV-ECU for DTCs other than P1A22.
- Retrieve and review freeze-frame data.
- Review freeze-frame Item No. 33, condenser voltage, in relation to total battery voltage as described in the Mitsubishi diagnostic material.
- Diagnose any additional EV-ECU DTCs found during the initial check.
13. Possible repair or resolution
- Not yet established by verified evidence. The supplied material provides diagnostic direction but does not provide a verified completed repair for P1A22.
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; available through NHTSA: https://static.nhtsa.gov/odi/tsbs/2019/MC-10158408-9999.pdf
- Mitsubishi TSB-19-54-004, published March 13, 2019; available through NHTSA: https://static.nhtsa.gov/odi/tsbs/2019/MC-10158409-9999.pdf
- Mitsubishi TSB-19-54-005, published March 13, 2019; available through NHTSA: 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 applicability: US-market Mitsubishi i-MiEV model years 2012, 2014, and 2016. Official manufacturer communications are published by NHTSA in TSB-19-54-003, TSB-19-54-004, and TSB-19-54-005.
19. Frequently asked questions
What does P1A22 mean on a Mitsubishi i-MiEV?
The supplied verified evidence identifies P1A22 within Mitsubishi EV-system diagnostic material, but it does not provide a complete plain-language fault definition.
What is the first documented diagnostic step for P1A22?
Use scan tool MB991958 to check whether DTCs other than P1A22 are stored in the EV-ECU.
Does the procedure use freeze-frame data?
Yes. The documented next step is to review freeze-frame data with scan tool MB991958, including Item No. 33, condenser voltage.
Can I drive or charge with P1A22?
Not yet established by verified evidence.
Which vehicles are supported by the supplied evidence?
US-market Mitsubishi i-MiEV model years 2012, 2014, and 2016.