01Jun JRC GPS Roll-Over - Affected equipment announcement

TNL would like to inform you of an upcoming GPS week number rollover event that will impact certain JRC navigation and communication units on 3rd August 2025.

Due to this event, the internal clock of affected units will revert to 23rd January 2005, which may result in abnormal system behavior, particularly in the display of date and functionality of communication features. Please note that this issue does not affect GPS positioning performance.

Affected Equipment (Rollover date: 3rd August 2025):

AIS: JHS-182 / JHS-183
GPS Navigator: JLR-7800 / JLR-7900
GPS Receiver: JLR-4341
GPS Compass: JLR-21 / JLR-31

Possible Effects:

Incorrect display of date and time information
Malfunction of certain communication functions

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* or JHS-183 replacement
AIS	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 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 Setting method of JLR-7900 Setting method of JLR-4341 Setting method of JLR-21/31
GPS Navigator	JLR-7900	All
GPS Receiver	JLR-4341	All
GPS Compass	JLR-21	All
GPS Compass	JLR-31	All