Do you own any GPS devices or use equipment that relies on GPS to function? If so, now is probably a good time to check whether or not those products are protected against the GPS Week Number Rollover issue — a sort of mini Y2K Bug for GPS receivers that will come into effect from April 6th this year.
The bug isn’t disastrous and should only hit a small number of GPS devices, but for those impacted the results could be severe, resetting the receiver’s time and corrupting its location data. Only older devices are at risk, though, and if you’re just using a commercial device the fix is quite simple: just check that its software is up to date.
TomTom has told customers “if you frequently update your device there’s no need to worry” as it’s already rolled out a fix. (You can also check if your device is affected using its serial number here.) Garmin says it’s been testing its devices for problems but that “the vast majority of Garmin GPS devices will handle the [event] without issues.” And an official memorandum from the Department of Homeland Security says any GPS receivers running the latest IS-GPS-200 standard and connected to UTC “should not be adversely affected.”
If you’re not sure about whether your device is covered, contact the manufacturer.
The rollover issue itself is caused by the fact that GPS systems count weeks using a ten-bit parameter. This means they start counting at week zero and reset when they hit week 1,024. The first count (or “GPS epoch”) started on January 6th, 1980, and the first reset took place on August 21st, 1999. That means the next one is due April 6th this year.
When the rollover happens older devices may reset their date, potentially corrupting navigation data and throwing off location estimates. GPS relies on precise timing data to operate, and each nanosecond the clock is out translates into a foot of location error.
More information about the GPS system here
Check your GPS manufacturer for more information