Dear Customers,
The GPS Week Number Rollover is approaching on 3rd August 2025. If your equipment isn't updated, it is ideal to fix the equipment before August 2025. This guide shows you how to check, update, or replace your GPS units to stay operational and avoid costly disruption.
The subject models are designed to turn the clock back 19.6 years (23rd January 2005) and may continue to function incorrectly under normal use.
However, there is no influence on positioning operation, and as a result, the following abnormalities may occur in some equipment:
- Some date information will be displayed erroneously.
- Communication function will not work properly.
*1 GPS week number rollover for equipment:
The week number counter in GPS resets once every 1023 weeks (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 counter rollover will occur
Need help with the Rollover? We Can Help
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 8th September 2024 at 00:00 AM (UTC).
| 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 Confirmation method of JUE-500 software version |
| GPS Navigator | JLR-7500 | All | Note that the 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 a rollover day. | When the time and date go back to the starting 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 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 the 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 the rollover day. | Upgrade the software or JHS-183 replacement |
| JHS-183 | NTE-183: up to BE04000 NCM-983: up to BB04206 |
Upgrade the software | ||
| 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 the rollover day. | When the time and date go back to the starting date, the equipment will return to normal operation by the following settings Setting method of JLR-7800 Setting method of JLR-7900 Setting method of JLR-4341 Setting method of JLR-21/31 |
| JLR-7900 | All | |||
| GPS Receiver | JLR-4341 | All | ||
| GPS Compass | JLR-21 | All | ||
| JLR-31 | All |
For the software update, the corresponding cost will be charged.