6 January 2011
Important notice to our customers who use FURUNO GPS receivers that are affected by GPS week number rollover problem
We thank you very much for your trust and continued support.
It is regretful to report 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 12th of December 2010. This may stem from 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:
9 GPS receiver, GPS plotter, GPS plotter/fishfinder:
GP-500MARK-2, GP-1800, GP-1800F, GP-1800MARK-2, GP-50, GP-50MARK-2, GP-70, GP-70MARK-2, PS-8000, PS-8000MARK-2, GP-188, GP-3000 and GP-3100
2. Natures of the positioning error and its cause:
Due to the problem of GPS week number roll-over, the above-listed equipment may have GPS position errors, including failure of GPS position acquisition, etc., on and after 12th of December 2010.
3. Procedure for checking the equipment and counter measures to be taken:
Please carry out the following counter measures:
i. Double-check whether your GPS equipment matches any of the equipment listed above.
ii. If applicable, please check if the equipment can generate position data.
iii. In the process "ii",
A. if you have no problem in receiving precise GPS position as well as correct date information (year, month and date), you may regard your equipment as working properly.
B. if you can obtain precise GPS position but erroneous date information (year, month and date), more precisely the year is described as 1991, your equipment is affected by GPS week number roll-over problem but has no defect in GPS positioning.
C. if there is a GPS position error, i.e., failure of GPS position acquisition, we would like you to cold start your equipment through menu procedure. By cold starting your equipment, the GPS equipment will regain position data in most cases. Please note, however, that even though you regain the GPS position acquisition, the date information remains erroneous.
4. If the problem persists even after all the above actions were taken, it seems to be more likely that the problem stems from defect other than GPS week number roll-over. If such is the case, we sincerely regret to advise you to contact your nearest point of contact of FURUNO. Our sincere apology for all the inconveniences caused.
Information about your nearest point of contact of FURUNO :
http://www.furuno.com/
GPS week number rollover:
The GPS system 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 12th of December 2010, and the week number was reset to the week 0, that is, 28th of April 1991.
(Source: http://www.furuno.co.jp/en/news/notice/20110106_001.html)