Mitsubishi P1B01
Return to Step 1. NO : The diagnosis is complete. DTC P1B04 Maximum cell voltage abnormality during charging DTC P1B05 Minimum cell voltage abnormality during charging DTC P1B07
Quick answer
For verified U.S.-market Mitsubishi i-MiEV model years 2012, 2014, and 2016, P1B01 is documented in Mitsubishi/NHTSA service material as a DTC checked again after connecting a quick-charging connector or gun. If it resets, the procedure directs technicians to return to Step 1; if it does not reset, the diagnosis is complete.
This page separates verified manufacturer/regulator evidence from supporting material. Unsupported causes, repairs or safety conclusions are not guessed.
Watch Videos
Relevant videos play here without leaving this diagnostic page.
No sufficiently relevant embeddable video has been accepted for this diagnostic yet.
Videos are supporting material and never override OEM or regulator evidence.
1. What does P1B01 mean?
For verified U.S.-market Mitsubishi i-MiEV model years 2012, 2014, and 2016, P1B01 is documented in Mitsubishi/NHTSA service material as a DTC checked again after connecting a quick-charging connector or gun. If it resets, the procedure directs technicians to return to Step 1; if it does not reset, the diagnosis is complete.
2. Technical explanation
The supplied official Mitsubishi service-bulletin evidence does not establish a plain-language component failure definition for P1B01. It does establish a diagnostic confirmation process: erase the DTC, connect the quick-charging connector/gun, then check whether P1B01 is stored or set again in the EV-ECU. A recurring P1B01 directs the technician back to the first diagnostic step. The evidence also cautions that CAN bus line problems can cause an incorrect DTC to be stored or set, and states that CAN bus lines should be diagnosed before this diagnosis.
3. What system is affected?
EV-ECU; quick-charging diagnostic process. A more specific failed system or component is not yet established by verified evidence.
4. How serious is this code?
Unknown. The supplied verified evidence does not assign a severity level.
5. Symptoms you may notice
- P1B01 may be stored or set again in the EV-ECU after the DTC is erased and the quick-charging connector/gun is connected.
- Other driver-visible symptoms are not yet established by verified evidence.
6. Possible causes
- A CAN bus line problem can cause an incorrect DTC to be stored or set, according to the official service-bulletin evidence.
- Any underlying cause of a recurring P1B01 beyond the CAN-bus caution 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. The official procedure uses connection of a quick-charging connector/gun as part of a controlled diagnostic confirmation process.
9. What you can safely do
- Arrange diagnosis by a qualified Mitsubishi EV service technician.
- Provide the technician with the stored code and note whether it returns after a quick-charge connection.
- Do not attempt high-voltage battery, EV-ECU, or CAN-bus repair yourself.
10. Step-by-step troubleshooting
- Official service evidence instructs technicians to diagnose CAN bus lines before this diagnosis because CAN issues may produce an incorrect DTC.
- The technician procedure then erases P1B01, connects the quick-charging connector/gun, and checks whether P1B01 returns in the EV-ECU.
- If P1B01 returns, the official procedure directs a return to Step 1. If it does not return, the diagnosis is complete.
11. When to contact service
Service is appropriate because the verified procedure requires EV-ECU DTC checking and CAN-bus diagnosis. High-voltage and network-system diagnosis should be performed by qualified personnel.
12. What the service center may check
- Check CAN bus lines before proceeding with the P1B01 diagnosis.
- Erase the stored or set DTC in the EV-ECU.
- Connect the quick-charging connector/gun as specified by the service procedure.
- Check whether P1B01 is stored or set again.
- If P1B01 returns, return to Step 1 of the applicable Mitsubishi procedure; if it does not return, the diagnosis is complete.
13. Possible repair or resolution
- No specific repair or replacement is established by the supplied verified evidence.
- The documented resolution path is diagnostic confirmation: a non-returning P1B01 after the prescribed check completes the diagnosis; a returning P1B01 requires restarting the procedure at Step 1.
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 as manufacturer communication MC-10158408.
- Mitsubishi TSB-19-54-004, published March 13, 2019; available through NHTSA as manufacturer communication MC-10158409.
- Mitsubishi TSB-19-54-005, published March 13, 2019; available through NHTSA as manufacturer communication MC-10158410.
16. Recall information
- No recall information is established by the supplied verified evidence.
17. Official manufacturer information
Official sources supplied: NHTSA-hosted Mitsubishi manufacturer communications TSB-19-54-003 (MC-10158408), TSB-19-54-004 (MC-10158409), and TSB-19-54-005 (MC-10158410), each published March 13, 2019.
19. Frequently asked questions
What does P1B01 mean?
The supplied official evidence does not establish a standalone plain-language failure definition. It identifies P1B01 as an EV-ECU DTC that is checked again after a quick-charging connection.
Can a CAN bus issue trigger P1B01 incorrectly?
Yes. The official procedure cautions that a problem in the CAN bus lines can cause an incorrect DTC to be stored or set.
What happens if P1B01 comes back after it is cleared?
The official procedure directs the technician to return to Step 1.
Which vehicles are verified as applicable?
The supplied applicability evidence identifies U.S. Mitsubishi i-MiEV model years 2012, 2014, and 2016.