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Clear out junk files and repair common Windows errorsFree Scan →Fix the driver behind crashes, sound loss and screen glitchesFind Drivers →Repair Windows errors before they cause bigger problemsFix Now →For a Seiko Astron GPS Solar Dual Time Chronograph with Caliber 5X63, charge the watch, use Button B for GPS time-zone adjustment, then check daylight saving time (DST) and set the second time zone if needed. First confirm that “5X63” appears on the case back: Astron models use different calibers and their controls can differ.
Follow Seiko’s official 5X63 Complete User Guide for the full button and hand-position diagrams; use the manual that matches your caliber if your watch behaves differently.
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Before you begin: confirm the caliber and charge
Check the code engraved on the case back. These steps apply specifically to Caliber 5X63, which Seiko identifies as its GPS Solar Dual Time Chronograph. Do not assume that another Astron or Astron chronograph has the same button operations.
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Expose the dial to light before attempting GPS reception. Seiko cautions that GPS reception consumes considerable energy, and the 5X63 will not start reception at a low charge. Press and release Button B to display the charge level; the watch indicates one of four levels. GPS reception is available at medium or full charge. If the watch is low, keep it in light until the multi-function indicator returns to the day-of-week display.
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- Secure Case Back: Screw Type
Seiko’s 5X63 guide gives these approximate charging times, which can vary somewhat by model. They are estimates, not guarantees.
| Light condition in Seiko’s guide | From stopped to full charge | From stopped to steady one-second hand movement | Light for one day’s operation once moving |
|---|---|---|---|
| 700 lux, general office fluorescent light | Not stated | Not stated | 3.5 hours |
| 3,000 lux, 30 W fluorescent light at 20 cm | 250 hours | 9.5 hours | 1 hour |
| 10,000 lux, cloudy-day sunlight or 30 W fluorescent light at 5 cm | 75 hours | 3 hours | 15 minutes |
| 100,000 lux, sunny-day direct sunlight | 30 hours | 1.5 hours | 10 minutes |
Source for charging estimates: Seiko Watch Corporation, 5X63 Complete User Guide, accessed 2026. Avoid exposing the watch to high temperatures while charging.
How to set the time and time zone with GPS
Use GPS zone adjustment when you have moved to a different region or want the watch to determine the local time zone. The operation updates the zone as well as the time and date.
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1Clear out junk files and repair common Windows errors2Fix the driver behind crashes, sound loss and screen glitches3Repair Windows errors before they cause bigger problems- Go outdoors where the watch has a clear view of the open sky.
- Hold Button B for three seconds. Release it when the seconds hand reaches the 30-second position. The multi-function indicator shows “4+” as reception begins.
- Point the watch face upward and wait. Zone adjustment can take up to two minutes, depending on reception conditions. The seconds hand indicates satellite acquisition.
- Check the result when reception ends: the seconds hand points to Y for success or N for failure for five seconds. A successful adjustment sets the time and date and applies the received region’s time-zone and DST information.
Near a time-zone boundary, the watch may select an adjacent zone. Seiko notes that some boundaries its system follows may not match local boundaries exactly; this does not by itself indicate a fault. Check the displayed zone and set it manually if necessary.
How to sync the exact time without changing the zone
If the selected zone is already correct, use time-only GPS correction. This updates the time, date, and day while keeping the current zone.
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- Go outdoors under an open sky.
- Hold Button A for three seconds and release it when the seconds hand reaches zero.
- Point the dial upward and wait for the reception result.
If you have changed regions, use zone adjustment rather than time-only correction. Time-only correction does not necessarily set DST automatically, so check the DST state if the watch is an hour off.
How to set the main-dial time zone manually
Manual zone selection is the fallback when GPS cannot determine the zone or has selected the wrong one.
- Pull the crown out to the first click. The seconds hand indicates the current main-dial zone.
- Turn the crown to the destination zone. Turning clockwise advances one zone; turning counterclockwise goes back one zone. Use Seiko’s time-zone list to match the seconds-hand position to the desired zone.
- Push the crown back in.
A manual zone change switches DST from automatic (“AT”) to a manual setting (“ST” for off or “DST” for on). Check and set DST for the region and date after selecting the zone.
How to set the second time zone
The 5X63’s six-o’clock sub-dial displays a second time zone when the stopwatch is not running. To choose its zone, pull the crown out to the second click, turn it until the seconds hand indicates the desired zone, then push the crown in. This selects a time zone; it is not an arbitrary minute-by-minute second clock.
Manual sub-dial zone selection also changes DST to an explicit on/off setting, so check the sub-dial’s DST state afterward. The watch also has a time-transfer function that swaps the main- and sub-dial times. Because the transfer affects which time is assigned to each dial, consult the transfer instructions in Seiko’s 5X63 guide before using it.
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- Powered by light energy, with no battery change required, this model has a 6-month power reserve once fully charged
- Case Diameter: 44.0mm
- The sunray finish black dial features chronograph and alarm subdials and perpetual calendar functions such as leap year, month, day, and date indicators
- The angular gold finish stainless steel case is paired with an integrated bracelet and includes a sapphire crystal and cabochon crown
- Water-resistant to 10 bar, 100 meters (330 feet)
How to check or change DST
The indicator uses “AT” for automatic DST, “ST” for DST off, and “DST” for DST on. For the main dial, pull the crown to the first click and hold Button A for three seconds to turn DST on; the hour and minute hands advance by one hour. Use the same operation to turn it off and set the indicator to ST. Seiko’s guide explains how to check the DST and zone status for each dial using the crown’s first and second clicks.
Do not assume every zone-setting operation leaves DST automatic: manual selection can switch the watch to an explicit on/off setting. Check the appropriate dial after changing its zone.
Using the chronograph
The 5X63 stopwatch measures up to 24 hours in 1/20-second increments. While the stopwatch is running, the six-o’clock sub-dial acts as a 24-hour counter; otherwise, it displays the second time zone. Seiko’s official manual has a dedicated “How to use the stopwatch” section with the start, stop, and reset operations. Follow that section rather than inferring controls from another Astron caliber.
5X63 specifications and operating expectations
Seiko lists a 38-city world-time function, GPS zone and time adjustment, time transfer, DST, power save, and a perpetual calendar through February 28, 2100 for the 5X63 HAB002. These are manufacturer specifications, not independent test results.
- Seiko specifies approximately six months of operation when fully charged and approximately two years in power-save mode for HAB002.
- Without GPS reception, Seiko specifies precision of ±15 seconds per month at temperatures between 5°C and 35°C.
Seiko’s May 12, 2026 announcement lists HAB001, HAB002, and HAB003 as continuous-production 5X63 models, and HAB004 as a 145th-anniversary limited edition of 2,000 pieces. The announcement said they would be available worldwide from June 2026; actual availability can vary by market and change over time.
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Sources: Seiko Watch Corporation, HAB002 product specifications and May 12, 2026 model announcement, accessed 2026.
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