Notice : GPS Week Number Rollover for equipment 2024
Dear valued customer
We would like to announce that GPS week number rollover ＊1 for equipment is to occur on some of our GPS’ on 8th September 2024 or 3rd August 2025.
The subject models are designed to turn the clock back 19.6 years (23th January 2005), and will continue to work incorrectly under normal use, however there is no influence on positioning operation.
However, as the results, the following abnormalities occur in some equipment.
- Some date information will be displayed erroneous.
- Communication function will not work properly.
For details, please see the 2. notice and countermeasures below.
*1 GPS week number rollover :
The week number counter in GPS resets once every 1023 weeks, which is approximately 19.6 years. The week number counters for the GPS in the objective equipment below started their week count from 23rd January 2005. It is on 8th September 2024 at 00:00 AM (UTC) that the week number counters rollover will occur.
1. Objective Equipment
1-1.Rollover date: 8th September 2024
- Inmarsat Fleet Broadband FB500（JUE-500）
- GPS navigator（JLR-7500/7600）
- GPS receiver（JLR-4331W/4340）
- GPS compass（JLR-20/30）
1-2.Rollover date: 3rd August 2025
- AIS（JHS-182/183）
- GPS navigator（JLR-7800/7900）
- GPS receiver（JLR-4341）
- GPS compass（JLR-21/31）
2. Notice and Countermeasures
2-1.The rollover day is on the 8th September 2024 at 00:00 AM (UTC)
The registration process to the Inmarsat network fails and communication becomes impossible.
The date of the internal clock and log function of the device returns to the starting date.
Upgrade the software *2
Confirmation method of JUE-500 software version
| Equipment | Models | Subject Serial No. | Notice | Countermeasures |
| Inmarsat Fleet Broadband FB250 | JUE-500 | All | The registration process to the Inmarsat network fails and communication becomes impossible. The date of the internal clock and log function of the device returns to the starting date. | Upgrade the software *2 |
| GPS Navigator | JLR-7500 | All | Note that time and date will go back to the starting date (January 23, 2005) when a master-reset of equipment or a battery replacement is carried out after rollover day. | When the time and date go back to the staring date, the equipment will return to normal operation by the following settings.Setting method of JLR-7500 Setting method of JLR-7600 Setting method of JLR-4331W Setting method of JLR-4340 Setting method of JLR-20/30 |
| JLR-7600 | All | |||
| GPS Receiver | JLR-4331W | After KE51719 | ||
| JLR-4340 | All | |||
| GPS Compass | JLR-20 | All | ||
| JLR-30 | All |
2-2. The rollover day is on the 3rd August 2025 at 00:00 AM (UTC)
| Equipment | Models | Subject Serial No. | Notice | Countermeasures |
| AIS | JHS-182 | JHS-182: after BB51401 NTE-182: after BB71401 | Note that time and date will go back to the starting date (December 18 ,2005) when a master-reset or restarting of equipment is carried out after rollover day. | Upgrade the software *2 or JHS-183 replacement |
| JHS-183 | NTE-183: up to BE04000 NCM-983: up to BB04206 | Upgrade the software *2 | ||
| GPS Navigator | JLR-7800 | All | Note that time and date will go back to the starting date (December 18 ,2005) when a master-reset of equipment or a battery replacement is carried out after rollover day. | When the time and date go back to the staring date, the equipment will return to normal operation by the following settings. Setting method of JLR-7800 |
| JLR-7900 | All | |||
| GPS Receiver | JLR-4341 | All | ||
| GPS Compass | JLR-21 | All | ||
| JLR-31 | All |
*2 : For more information, and countermeasures, please contact our service agents or sales representatives.
For the software update, the corresponding cost will be charged.
SOURCE : JRC / ALPHATRON