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14 February 2013

Important notice to our customers who use FURUNO GPS receivers for marine use that are affected by GPS week number rollover. [eRideOPUS GPS & GNSS receivers are not affected by this matter.]

We thank you very much for your trust and continued support.

It is regretful to announce that there is a possibility that some of our GPS receivers and GPS-incorporated equipment (please see the list below) may face GPS positioning errors after 11th of August 2013, due to the problem of GPS week number roll-over. If you happened to spot any GPS positioning error on the equipment listed below, we would like to ask you to take the following countermeasures to resolve the problem. If the problem persisted after having taken the countermeasures, please consult with our sales representative closest to your location. We sincerely apologize for all the inconveniences caused.

1. List of equipment that may be affected by the GPS week number roll-over:
< GPS receiver, GPS plotter, GPS plotter/fishfinder >
GP-500MARK-2, GP-1800, GP-1800F, GP-1800MARK-2, GP-188, GP-3000, GP-3050, GP-3100, GP-3100MARK-2, GP-3300, GP-500MARK-2, GP-70MARK-2, GP-8000, GP-8000MARK-2, PS-1000, PS-1000S, PS-8000, PS-8000MARK-2, FRS-1000A, FRS-1000B, FRS-1000C, GP-1600, GP-1600F, GP-1610C, GP-1610CF, GP-1810, GP-1810F, GP-3210, GP-80, RS-1000A and RS-1000C

< Inmarsat C mobile earth station >

< Current indicator >

2. Natures of the positioning error and its cause:
The GPS system is synchronized to a different time scale than Coordinated Universal Time (UTC) and calculates time by counting the number of weeks up to 1,023rd week. After week 1,023, the week number count is reset to zero. This is called "GPS week number rollover". This rollover occurred to some of the GPS receivers listed above on the 11th of August 2013, and the week number was reset to the week 0, that is, 26th of December 1993. Subsequently, the erroneous date information on the GPS receiver clock may result in instability in positioning, causing position errors, including failure of GPS position acquisition, etc.

3. Procedure for checking the integrity of the equipment and counter measures to be taken:
Please carry out the following counter measures:

i. Since the nature of the problem of "GPS week number roll-over" is the erroneous date information on the receiver clock, the equipment that does not require date information would be unaffected by the problem in question. If, by any chance, the positioning performance became instable, you would be able to resolve the problem of positioning integrity by cold-starting the equipment through the operating menu. Please note, however, that even though you regain the GPS position acquisition, the date information cannot be restored merely by cold-starting.

ii. If the positioning integrity is not restored after cold start, the problem may stem from the failure of the equipment, not from GPS week number roll-over. If such is the case, please consult with our sales representative closest to your location.

iii. If you wish to restore the date information, you will need to replace the GPS receiver within the equipment for value. Also, please note that the above list of equipment includes some models whose maintenance service provision period has been expired.

< Note >
If the GPS receiver is interfaced with any of the following equipment and systems, the countermeasures would have to be taken, for the date information is utilized by the interfaced equipment and systems:
1. GMDSS radio installation (inclusive of internal GPS receiver of Inmarsat C terminal)
2. Ship Security Alert System (SSAS)
3. Vessel Monitoring System (VMS)
4. Equipment that present route information such as ECDIS
5. Voyage Data Recorder (VDR)
6. Automatic Identification System (AIS)
7. Other equipment and systems that utilizes the date information from GPS receiver clock

For further information and consultation, please contact your nearest point of contact of FURUNO. Our sincere apology for all the inconveniences caused.

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Information about your nearest point of contact of FURUNO:

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