Citizen AP1055-87L
Citizen Chronograph Blue Dial Men's Watch AP1055-87L User Manual
Model: AP1055-87L
Introduction
Thank you for choosing the Citizen Chronograph Blue Dial Men's Watch AP1055-87L. This manual provides essential information for the proper setup, operation, and maintenance of your new timepiece. Please read it thoroughly to ensure optimal performance and longevity of your watch.

Figure 1: Citizen Chronograph Blue Dial Men's Watch AP1055-87L
This image displays the Citizen AP1055-87L watch, highlighting its distinctive blue dial with gold-tone luminous hands, the black IP stainless steel case, and the matching black IP stainless steel band. The watch features multiple subdials for chronograph functions and a moon phase indicator.
Product Overview
The Citizen AP1055-87L is a sophisticated men's chronograph watch featuring Citizen's Eco-Drive technology, which powers the watch using any light source, eliminating the need for battery replacement. It boasts a durable black IP stainless steel case and band, a scratch-resistant sapphire crystal, and is water-resistant up to 50 meters (165 feet).
- Movement: Eco-Drive (Light-powered)
- Case Material: Black IP Stainless Steel
- Band Material: Black IP Stainless Steel
- Crystal: Scratch Resistant Sapphire
- Water Resistance: 50 meters / 165 feet
- Dial: Blue with Luminous Gold-tone Hands
- Clasp: Buckle
- Crown: Pull / Push
- Case Dimensions: 42 mm diameter x 10.1 mm thickness
Setup
Initial Charge
As an Eco-Drive watch, your Citizen AP1055-87L is powered by light. Before initial use, ensure the watch is fully charged by exposing the dial to bright light (natural or artificial) for several hours. Avoid direct sunlight for prolonged periods to prevent overheating.
- For a full charge from a completely stopped state, expose to direct sunlight for approximately 11 hours, or to a fluorescent lamp (30W, 20cm distance) for about 50 hours.
- A typical daily charge requires exposure to direct sunlight for about 2 hours, or to a fluorescent lamp for about 10 hours.
Setting the Time and Date
- Pull the crown out to the first click position to adjust the date. Turn the crown to set the correct date.
- Pull the crown out to the second click position to adjust the time. Turn the crown to move the hands clockwise until the correct time is displayed. Ensure AM/PM is correctly set if your watch has a 24-hour indicator or moon phase that changes with AM/PM.
- Push the crown back in to the normal position to start the watch.
Adjusting the Band
The black IP stainless steel band may require adjustment for a comfortable fit. This typically involves removing or adding links. It is recommended to have this procedure performed by a qualified jeweler or Citizen service center to prevent damage to the band or clasp.
Operating Instructions
Chronograph Function
Your watch features a chronograph, which allows for precise timing of events. The specific operation may vary slightly depending on the subdial layout. Refer to the markings on your watch for specific functions (e.g., 60-second, 60-minute, 24-hour subdials).
- Start/Stop: Press the upper pusher (button) to start and stop the chronograph.
- Reset: Press the lower pusher while the chronograph is stopped to reset all chronograph hands to zero.
Moon Phase Indicator
The moon phase indicator displays the current phase of the moon. This complication is typically set in conjunction with the date and time, and once set, it will advance automatically with the passage of days.
To set the moon phase, consult a current moon phase calendar. Pull the crown to the appropriate position (often the first click, or a dedicated pusher if available) and rotate to align the moon phase indicator with the current moon phase. Push the crown back in when complete.
Water Resistance
This watch is water-resistant to 50 meters (165 feet). This rating means it is suitable for short periods of recreational swimming, but not for diving or snorkeling. Avoid operating the crown or pushers while the watch is wet or submerged.
| Rating | Activity |
|---|---|
| 30m (3 ATM) | Splash resistant, rain |
| 50m (5 ATM) | Short periods of recreational swimming |
| 100m (10 ATM) | Swimming, snorkeling |
| 200m+ (20 ATM+) | Diving |
Maintenance
Cleaning Your Watch
Regular cleaning helps maintain the appearance and longevity of your watch. Use a soft, dry cloth to wipe the case and crystal. For the metal band, a slightly damp cloth can be used, followed by a dry cloth. Avoid using harsh chemicals or abrasive materials.
Storage
When not wearing your watch, store it in a place where it can be exposed to light periodically to maintain its charge. Avoid extreme temperatures, direct sunlight for prolonged periods, and strong magnetic fields.
Periodic Inspection
It is recommended to have your watch inspected by an authorized Citizen service center every 2-3 years. This inspection can include checking the water resistance, cleaning, and general maintenance to ensure continued optimal performance.
Troubleshooting
| Problem | Possible Cause | Solution |
|---|---|---|
| Watch has stopped or is running intermittently. | Insufficient charge. | Expose the watch dial to bright light for several hours to fully charge. |
| Hands are not moving correctly after setting. | Crown not fully pushed in. | Ensure the crown is pushed all the way back into the normal position. |
| Chronograph hands do not reset to zero. | Requires chronograph reset procedure. | Press the lower pusher while the chronograph is stopped to reset. If this does not work, consult a service center. |
| Condensation under the crystal. | Exposure to extreme temperature changes or compromised water resistance. | Immediately take the watch to an authorized service center for inspection and repair to prevent internal damage. |
Specifications
- Model Number: AP1055-87L
- Movement: Citizen Eco-Drive
- Case Material: Black IP Stainless Steel
- Case Diameter: 42 mm
- Case Thickness: 10.1 mm
- Band Material: Black IP Stainless Steel
- Crystal: Sapphire
- Water Resistance: 50 meters (165 feet)
- Dial Color: Blue
- Hands: Luminous Gold-tone
- Functions: Chronograph, Date, Day, Moon Phase, Hour, Minute, Second
- Clasp Type: Buckle
Warranty and Support
Warranty Information
Citizen watches typically come with a limited international warranty covering manufacturing defects. The duration and terms of the warranty may vary by region. Please refer to the warranty card included with your purchase for specific details and registration instructions. Keep your proof of purchase for warranty claims.
Customer Support
For further assistance, service, or repair, please contact Citizen customer support or visit an authorized Citizen service center. You can find contact information and service center locations on the official Citizen website:
Visit Citizen Official Website
When contacting support, please have your watch model number (AP1055-87L) and purchase details ready.
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