# Service bulletin B20\-050

A bulletin is a manufacturer's communication to its dealers, as NHTSA indexes it. The summary is NHTSA's. The document is the manufacturer's: read it at NHTSA. A bulletin is not a recall, and listing a model year does not mean every vehicle of it is concerned.

- Type: Service bulletin
- NHTSA id: 10184335
- Published by NHTSA: 2020\-12\-19
- Manufacturer's number: B20\-050
- Manufacturer's date: 2020\-12\-09
- NHTSA component: ENGINE AND ENGINE COOLING; ELECTRICAL SYSTEM

## NHTSA's summary

Service Bulletin \- The vehicle may not start upon first press of the ENGINE START/STOP button. Also, MID displays the error message KEYLESS START SYSTEM ERROR, and DTC B12C5 \(Engine Start/Stop Switch Failure\) is stored. American Honda is extending the warranty for the keyless start system on these vehicles to 9 years from the original date of purchase or 125,000 miles, whichever comes first.

## The document

- [NHTSA's copy of the document (PDF)](https://static.nhtsa.gov/odi/tsbs/2020/MC-10184335-0001.pdf)
- [If that address does not open, try this one](https://static.nhtsa.gov/odi/tsbs/2020/MC-10184335-9999.pdf)

The document is the manufacturer's. This site does not hold it.

## Components

Electrical system, Engine

## Trouble codes named

B12C5

## Vehicles listed

- 2017 ACURA NSX

## Recalls for the same vehicles and component

- [18V599000](/recalls/nhtsa/18V599000.md), 2018-09-07: EXTERIOR LIGHTING:BRAKE LIGHTS; ELECTRICAL SYSTEM:WIRING:FUSES AND CIRCUIT BREAKERS
- [2018478](/recalls/tc/2018478.md), 2018-09-06: Electrical

## Other bulletins for the same vehicles and component

- [ONL6NZ01252023](/bulletins/10231060.md), 2023-02-04, Service bulletin: ELECTRICAL SYSTEM; FUEL SYSTEM, GASOLINE. Owner Notification Letter \- Our records indicate that a Product Update has not been completed on this vehicle \(Vehicle Identification Number \[VIN NUMBER\]\). The PGM\-FI computer may not output some required communication data to a generic scan tool under certain conditions due to an internal software defect. This has no effect on the function or use of the vehicle.
- [B21\-036](/bulletins/10219525.md), 2022-09-09, Service bulletin: ELECTRICAL SYSTEM. "Service bulletin \- Due to a software defect between two CPUs, the Generic Scan Tool \(GST\) may not be able to read the Calibration ID \(CID\) of the CPU under some limited conditions. NOTE: The GST issue doesn't impact the Honda scan tool."
- [ONL6NZ01212022](/bulletins/10206809.md), 2022-01-26, Service bulletin: ELECTRICAL SYSTEM. Owner Notification Letter \- On your 2017 or 2018 NSX, the PGM\-FI computer may not output some required communication data to a generic scan tool under certain conditions, due to an internal software defect. This has no effect on the function or use of the vehicle. For customers who may be subject to inspection maintenance or Smog Check, this issue may cause you to fail an inspection.
- [BBOM11242021](/bulletins/10203803.md), 2021-12-03, Service bulletin: ELECTRICAL SYSTEM; ELECTRICAL SYSTEM:SOFTWARE. Dealer Message \- Today, November 24, 2021, Acura is announcing a product update for certain 2017\-2018 NSX vehicles for a software defect that may prevent the output of the calibration ID \(CID\) to a generic scan tool \(GST\). Perform an iN VIN status inquiry to determine which units in your inventory are affected.
- [B21\-036](/bulletins/10203802.md), 2021-12-03, Service bulletin: ELECTRICAL SYSTEM; ELECTRICAL SYSTEM:SOFTWARE. Service Bulletin \- Due to a software defect between two CPUs, the Generic Scan Tool \(GST\) may not be able to read the Calibration ID \(CID\) of the CPU under some limited conditions.
- [ONLX8Z02162021](/bulletins/10187550.md), 2021-02-26, Service bulletin: EQUIPMENT; ELECTRICAL SYSTEM; ENGINE AND ENGINE COOLING. Owner Notification Letter \- The vehicle may not start upon first press of the ENGINE START/STOP button. Also, the MID displays the error message KEYLESS START SYSTEM ERROR, and DTC B12C5 \(Engine Start/Stop Switch Failure\) is stored. American Honda is extending the warranty on the engine start/stop switch to 9 years from the original date of purchase or 125,000 miles, whichever comes first.
- [BBOM12092020](/bulletins/10184336.md), 2020-12-19, Service bulletin: EQUIPMENT; ENGINE AND ENGINE COOLING; ELECTRICAL SYSTEM. Dealer Message \- Today, December 9, 2020, Acura is announcing a warranty extension for certain 2017 NSX vehicles. This warranty extension covers the engine start/stop switch to address concerns of difficulty in starting or stopping the engine. Acura is extending the warranty coverage of the engine start/stop switch to 9 years from the original date of purchase or 125,000 miles, whichever comes first.
- [ONL6EL02142020\_1](/bulletins/10171556.md), 2020-02-20, Service bulletin: EQUIPMENT:OTHER:OWNERS/SERVICE/OTHER MANUAL; ENGINE AND ENGINE COOLING; ELECTRICAL SYSTEM. Owner Notification Letter \- During assembly, the Owner Information CD that was placed in the vehicle did not include all the required emissions components in the Emissions Warranty Parts List. Enclosed in this package is an updated Owner Information CD that includes the updated Emission Warranty Parts List. Please place this CD in your vehicle glove box and discard the original Owner Information CD.
- [BBOM12122019](/bulletins/10169502.md), 2019-12-18, Service bulletin: FUEL SYSTEM, GASOLINE; ELECTRICAL SYSTEM; ENGINE AND ENGINE COOLING. Dealer Message \- Today, American Honda is announcing a product update \(PUD\) for certain 2017\-19 NSX vehicles due to warranty booklets or CDs that do not list the correct warranty coverage for some emissions components. Do an iN VIN status inquiry to determine which units in your inventory are affected.
- [B19\-069](/bulletins/10169501.md), 2019-12-18, Service bulletin: FUEL SYSTEM, GASOLINE; ELECTRICAL SYSTEM; ENGINE AND ENGINE COOLING. Service Bulletin \- The warranty information booklet or CD that was placed in the vehicle during assembly did not include all the required emissions components in the Emissions Warranty Parts List. The failure to include the missing parts in the Emissions Warranty Parts List may cause confusion and client dissatisfaction.

JSON: [/v1/bulletins/10184335](/v1/bulletins/10184335)

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