Mitsubishi P1B04
Return to Step 1. NO : The diagnosis is complete. DTC P1B06 Maximum cell temperature abnormality during charging CAUTION If there is any problem in the CAN bus lines, an incorrect
Quick answer
P1B04 is documented in Mitsubishi service material as a DTC checked after charging. The supplied evidence does not establish a standalone meaning for P1B04; the title/meaning text appears to contain adjacent diagnostic-procedure content for P1B06. Mitsubishi directs technicians to diagnose CAN bus faults first because an incorrect DTC may be stored if CAN communication has a problem.
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 P1B04 mean?
P1B04 is documented in Mitsubishi service material as a DTC checked after charging. The supplied evidence does not establish a standalone meaning for P1B04; the title/meaning text appears to contain adjacent diagnostic-procedure content for P1B06. Mitsubishi directs technicians to diagnose CAN bus faults first because an incorrect DTC may be stored if CAN communication has a problem.
2. Technical explanation
For applicable Mitsubishi i-MiEV vehicles, the supplied official service-bulletin excerpts describe a verification step: erase stored DTCs, charge using the regular/normal or quick-charge connector, then check the EV-ECU again. If P1B04, P1B05, or P1B07 is stored/set again, the procedure returns to Step 1; if not, diagnosis is complete. The excerpts also state that the BMU communicates with the EV-ECU via CAN and that CAN bus lines must be diagnosed before the referenced diagnosis because CAN faults can result in an incorrect DTC.
3. What system is affected?
BMU-to-EV-ECU communication via the CAN bus is explicitly referenced. A specific P1B04 subsystem is not yet established by verified evidence.
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
- A CAN bus line problem can cause an incorrect DTC to be stored or set, according to the supplied Mitsubishi service information.
- Any further cause specific to P1B04 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 supplied service procedure includes charging as part of a technician diagnostic confirmation process.
9. What you can safely do
- Arrange diagnosis by a qualified Mitsubishi EV service provider.
- Provide the technician with the stored DTC information and whether P1B04 returns after charging.
- Do not attempt high-voltage battery, BMU, EV-ECU, or CAN wiring repairs yourself.
10. Step-by-step troubleshooting
- Mitsubishi service information instructs that CAN bus lines be diagnosed before the referenced diagnostic procedure.
- The documented confirmation sequence is: erase the DTCs, charge using the regular/normal or quick-charge connector, then recheck the EV-ECU for DTCs.
- If P1B04, P1B05, or P1B07 returns, the documented procedure says to return to Step 1. If it does not return, the diagnosis is complete.
11. When to contact service
Contact a qualified Mitsubishi EV service provider. CAN-bus diagnosis and EV battery-system work should be performed by trained personnel.
12. What the service center may check
- Check for CAN bus line problems before the referenced diagnosis, because CAN faults may store an incorrect DTC.
- Erase stored DTCs and recharge using a regular/normal or quick-charge connector.
- Recheck the EV-ECU to determine whether P1B04, P1B05, or P1B07 is stored/set again.
13. Possible repair or resolution
- If the DTC does not return after the documented erase, charge, and recheck sequence, the supplied procedure states that diagnosis is complete.
- A specific repair for P1B04 is 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 manufacturer 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 P1B04 mean?
The supplied verified excerpts do not establish a standalone definition for P1B04. They identify P1B04 as one of the DTCs checked after charging during Mitsubishi’s diagnostic process.
Could a CAN fault affect this code?
Yes. The supplied Mitsubishi service information states that a CAN bus line problem can cause an incorrect DTC to be stored or set, and instructs technicians to diagnose CAN bus lines first.
Which vehicles are covered by the supplied applicability data?
Mitsubishi i-MiEV, U.S. market, model years 2012, 2014, and 2016.