NHTSA Service Bulletin 10191951: 2019-2021 Nissan Altima
Official manufacturer communication context for 2019-2021 Nissan Altima, with affected products, buyer checks and links into Carchieve recall, problem and VIN research.
Reviewed June 2026 from NHTSA manufacturer communication and service bulletin records. Carchieve is independent and not affiliated with any vehicle manufacturer or government agency.
2019-2021 ALTIMA AND 2021 ROGUE; AC INOPERATIVE WITH DTC B20C8-14 STORED IF YOU CONFIRM The AC compressor is not engaging when the AC is in the ON position as indicated by the yellow illumination on the AC button, And DTC B20C8-14 ECV (ELECTRICAL CONTROL VALVE) is stored in the IPDM. SERVICE PROCEDURE 1. Clear the DTC, and follow the DTC CONFIRMATION PROCEDURE in the ESM. If DTC B20C8-14 is past, AC compressor operation is inhibited until the DTC is cleared. If DTC B20C8-14 returns after being cleared (either Current or Past status), follow the ESM diagnosis procedure. For models with Automatic Air Conditioning, go to section: VENTILATION, HEATER & AIR CONDITIONER > HEATER & AIR CONDITIONING CONTROL SYSTEM > AUTOMATIC AIR CONDITIONING > DTC/CIRCUIT DIAGNOSIS > B20C8-14 ECV (ELECTRICAL CONTROL VALVE). For models with Manual Air Conditioning, go to section: VENTILATION, HEATER & AIR CONDITIONER > HEATER & AIR CONDITIONING CONTROL SYSTEM > MANUAL AIR CONDITIONING > DTC/CIRCUIT DIAGNOSIS > B20C8-14 ECV (ELECTRICAL CONTROL VALVE).
What this bulletin may mean before buying
Treat this as service research, not a verdict on one car. Before you buy, compare this communication with official recall campaigns, model-level owner complaint patterns, and the exact vehicle’s VIN-decoded specifications. A bulletin can help you ask a seller or dealer sharper questions about software updates, known repairs, warranty extensions and service history.
Affected products listed in this communication
Buyer checklist
- Run the 17-character VIN and confirm the year, make, model, engine and equipment match the listing.
- Check recall campaign pages for safety actions that may require dealer repair.
- Compare this bulletin with common problem pages for the same model and component area.
- Ask the seller or dealer whether the bulletin procedure, update or inspection has already been completed.
- Use the used-car buying checklist and get an independent inspection.
Frequently asked questions
What is NHTSA service bulletin 10191951?
2019-2021 ALTIMA AND 2021 ROGUE; AC INOPERATIVE WITH DTC B20C8-14 STORED IF YOU CONFIRM The AC compressor is not engaging when the AC is in the ON position as indicated by the yellow illumination on the AC button, And DTC B20C8-14 ECV (ELECTRICAL CONTROL VALVE) is stored in the IPDM. SERVICE PROCEDURE 1. Clear the DTC, and follow the DTC CONFIRMATION PROCEDURE in the ESM. If DTC B20C8-14 is past, AC compressor.
Is a service bulletin the same as a recall?
No. A recall is a safety campaign with a required remedy for affected VINs. A service bulletin or manufacturer communication usually describes diagnostic, repair, software, warranty or service information.
How should a used-car buyer use this bulletin?
Use it as a research signal. Compare it with recalls, owner complaints, service records, a VIN report and an independent inspection before buying.
Check the exact VIN before you buy
Model-level pages show public safety patterns. A full VIN report helps confirm the exact vehicle, decoded specs, recall applicability and buyer checks.
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