# Service bulletin N639NAS1

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: 10204094
- Published by NHTSA: 2021\-12\-07
- Manufacturer's number: N639NAS1
- Manufacturer's date: 2021\-11\-18
- NHTSA component: ELECTRICAL SYSTEM

## NHTSA's summary

A potential issue has been identified on specific vehicles where, in locations where the vehicle has poor or no network connection, vehicles may experience intermittent resetting of the navigation system, following a recent Map Over The Air \(MOTA\) update. The navigation screen displayed on the Touchscreen will revert to the PIVI home screen and the navigation screen displayed in the instrument cluster panel will revert to displaying the manufacturer's logo. The system will self\-recover and navigation will resume, however this fault may re\-occur if the vehicle maintains poor or no network connection. No other vehicle features or systems are affected.

## The document

- [NHTSA's copy of the document (PDF)](https://static.nhtsa.gov/odi/tsbs/2021/MC-10204094-0001.pdf)
- [If that address does not open, try this one](https://static.nhtsa.gov/odi/tsbs/2021/MC-10204094-9999.pdf)

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

## Components

Electrical system

## Vehicles listed

- 2020 to 2022 LAND ROVER DEFENDER
- 2021 to 2022 LAND ROVER DISCOVERY
- 2021 to 2022 LAND ROVER DISCOVERY SPORT
- 2021 to 2022 LAND ROVER RANGE ROVER EVOQUE
- 2021 to 2022 LAND ROVER RANGE ROVER VELAR

## Recalls for the same vehicles and component

- [26V599000](/recalls/nhtsa/26V599000.md), 2026-09-17: ELECTRICAL SYSTEM:PROPULSION SYSTEM:DC/DC CONVERTER
- [26V248000](/recalls/nhtsa/26V248000.md), 2026-04-17: ELECTRICAL SYSTEM:PROPULSION SYSTEM:DC/DC CONVERTER
- [22V581000](/recalls/nhtsa/22V581000.md), 2022-08-04: ELECTRICAL SYSTEM:ADAS
- [2021381](/recalls/tc/2021381.md), 2021-06-17: Electrical
- [21V457000](/recalls/nhtsa/21V457000.md), 2021-06-17: ELECTRICAL SYSTEM:12V/24V/48V BATTERY
- [21V424000](/recalls/nhtsa/21V424000.md), 2021-06-03: ELECTRICAL SYSTEM:SOFTWARE; POWER TRAIN:AUTOMATIC TRANSMISSION:CONTROL MODULE \(TCM/PCM/TECM\)

## Other bulletins for the same vehicles and component

- [N861 Range Rover 15MAY26](/bulletins/11033423.md), 2026-06-04, Other: ELECTRICAL SYSTEM. 48V Mild Hybrid Electric Vehicle \(MHEV\) battery enters an offline state and no longer communicates or functions as intended.
- [N811 Discovery 15MAY26](/bulletins/11033422.md), 2026-06-04, Other: ELECTRICAL SYSTEM. Door Zone Module \- Quiescent Drain
- [N811 Defender 15MAY26](/bulletins/11033398.md), 2026-06-04, Other: ELECTRICAL SYSTEM. Door Zone Module \- Quiescent Drain
- [N811 Discovery 17APR26](/bulletins/11032422.md), 2026-05-07, Other: ELECTRICAL SYSTEM. Door Zone Module \- Quiescent Drain
- [N811 Defender 17APR26](/bulletins/11032421.md), 2026-05-07, Other: ELECTRICAL SYSTEM. Door Zone Module \- Quiescent Drain
- [N869 Range Rover 20MAR26](/bulletins/11031114.md), 2026-04-07, Other: ELECTRICAL SYSTEM. Software Over The Air \(SOTA\) updates are failing to complete.
- [N869 DISCOVERY 20MAR26](/bulletins/11031113.md), 2026-04-07, Other: ELECTRICAL SYSTEM. Software Over The Air \(SOTA\) updates are failing to complete.
- [N811 Defender 20MAR26](/bulletins/11031092.md), 2026-04-07, Other: ELECTRICAL SYSTEM. Door Zone Module \- Quiescent Drain
- [SSM76411 \- 10MAR26](/bulletins/11030751.md), 2026-04-06, Other: ELECTRICAL SYSTEM. Smart Key Deactivated message on instrument cluster and unable to start their vehicle
- [Range Rover\_N861 02\-20\-20](/bulletins/11029857.md), 2026-03-06, Other: ELECTRICAL SYSTEM. The 48V Mild Hybrid Electric Vehicle \(MHEV\) battery enters an offline state and no longer communicates or functions as intended. This can result in illumination of the Malfunction Indicator Lamp \(MIL\), loss of start/stop functionality and no communication during diagnostic sessions.

JSON: [/v1/bulletins/10204094](/v1/bulletins/10204094)

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