Mitsubishi B1406
52B-004 Please make the indicated changes to the 2016 and 2017 i-MiEV Service Manual, Group 52B - Supplemental Restraint System (SRS) -> SRS Air Bag Diagnosis -> Diagnostic Trouble
Quick answer
For Mitsubishi i-MiEV vehicles covered by the verified evidence, DTC B1406 is addressed in SRS air bag diagnostic-procedure service-manual corrections. The verified bulletins instruct technicians to replace incorrect diagnostic information with corrected information; they do not establish a vehicle fault cause, symptoms, driveability status, or repair outcome.
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 B1406 mean?
For Mitsubishi i-MiEV vehicles covered by the verified evidence, DTC B1406 is addressed in SRS air bag diagnostic-procedure service-manual corrections. The verified bulletins instruct technicians to replace incorrect diagnostic information with corrected information; they do not establish a vehicle fault cause, symptoms, driveability status, or repair outcome.
2. Technical explanation
Verified NHTSA-posted Mitsubishi communications identify B1406 within Group 52B, Supplemental Restraint System (SRS), under SRS Air Bag Diagnosis and SRS-ECU diagnostic trouble code procedures. For 2016–2017 U.S. i-MiEV models, TSB-18-52B-004 directs a correction to the B1406 and B1416 diagnosis information in the service manual. Separate bulletins provide equivalent manual-diagnosis corrections for 2012 and for 2013–2014 i-MiEV coverage described in those bulletins.
3. What system is affected?
Supplemental Restraint System (SRS), specifically SRS air bag diagnosis and SRS-ECU DTC procedures.
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
- Not yet established by verified evidence. The supplied official bulletins establish that diagnostic information for B1406 required correction, but do not provide the corrected fault cause in the supplied 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 using the applicable Mitsubishi i-MiEV SRS service information and the relevant official bulletin.
- Do not attempt air bag or SRS component repair based on the supplied evidence.
10. Step-by-step troubleshooting
- For a 2016–2017 U.S. i-MiEV, use TSB-18-52B-004 when consulting the Group 52B SRS-ECU DTC B1406 diagnostic procedure.
- For 2012 i-MiEV coverage, consult TSB-18-52B-002.
- For 2013–2014 i-MiEV coverage described by the bulletin, consult TSB-18-52B-003.
- The detailed corrected diagnostic steps are not contained in the supplied evidence summary; further fault-isolation steps are not yet established by verified evidence.
11. When to contact service
Service involvement is not explicitly required by the supplied evidence. However, B1406 concerns SRS diagnostic procedures, and the verified information supports using the applicable Mitsubishi bulletin and service-manual correction for diagnosis.
12. What the service center may check
- Confirm the vehicle model year and market applicability before selecting the bulletin.
- Confirm that B1406 is retrieved from the SRS-ECU.
- Use the corrected B1406 diagnostic information specified by the applicable TSB rather than the superseded service-manual information.
13. Possible repair or resolution
- Not yet established by verified evidence.
14. Affected vehicles
- Mitsubishi i-MiEV · 2012 · US
- Mitsubishi i-MiEV · 2013–2014 · US
- Mitsubishi i-MiEV · 2016–2017 · US
15. Related TSBs / service bulletins
- TSB-18-52B-004, published December 20, 2018: Applies to the 2016–2017 i-MiEV Service Manual, Group 52B. It instructs replacement of incorrect B1406 and B1416 diagnosis information with corrected information in SRS-ECU DTC procedures. NHTSA document: https://static.nhtsa.gov/odi/tsbs/2018/MC-10152961-9999.pdf
- TSB-18-52B-002, published December 20, 2018: Applies to the 2012 i-MiEV Service Manual, Group 52B, and corrects B1406 and B1416 diagnosis information. NHTSA document: https://static.nhtsa.gov/odi/tsbs/2018/MC-10152960-9999.pdf
- TSB-18-52B-003, published December 20, 2018: Covers corrections for B1406 and B1416 diagnosis information in Group 52B for the 2013 (Canada only) and 2014 i-MiEV Service Manual. NHTSA document: https://static.nhtsa.gov/odi/tsbs/2018/MC-10152959-9999.pdf
16. Recall information
- Not yet established by verified evidence.
17. Official manufacturer information
Official evidence consists of NHTSA-posted Mitsubishi manufacturer communications TSB-18-52B-002, TSB-18-52B-003, and TSB-18-52B-004, all published December 20, 2018. The supplied evidence confirms a correction to B1406 diagnostic information, not a recall or a specific component replacement.
19. Frequently asked questions
What system is associated with B1406 in the supplied Mitsubishi evidence?
It is associated with Group 52B, Supplemental Restraint System (SRS), including SRS air bag diagnosis and SRS-ECU DTC procedures.
Does the verified evidence identify the exact cause of B1406?
No. The supplied bulletin summaries confirm that B1406 diagnostic information was corrected, but do not state the specific fault cause.
Which bulletin applies to a 2016 or 2017 U.S. i-MiEV?
TSB-18-52B-004 is the verified bulletin for 2016–2017 i-MiEV service-manual corrections.
Is B1406 an EV battery or charging-system code according to the supplied evidence?
No such classification is established. The supplied evidence places B1406 in SRS diagnostic procedures.