Class A AIS Troubleshooting: Common Faults and Quick Solutions for Onboard Personnel
Class A AIS Troubleshooting: Common Faults and Quick Solutions for Onboard Personnel
For onboard personnel, timely handling of Class A AIS faults is crucial to ensuring continuous operation of the equipment and voyage safety. Even high-quality Class A AIS may encounter occasional faults due to harsh marine environments, improper operation, or component aging. This article summarizes common Class A AIS faults, their causes, and quick troubleshooting methods to help onboard personnel resolve problems efficiently.
Common Class A AIS Faults and Causes
Based on on-site statistics from maritime technical support teams, the most common Class A AIS faults include the following types:
No Power Supply or Failure to Start: The main causes include loose power cable connections, damaged power sockets, exhausted emergency power supplies, or faulty power modules of the AIS host. In severe cases, it may be caused by short circuits due to water ingress into the equipment.
Positioning Failure (No GPS/Beidou Signal): Manifested as "position unknown" or "signal loss" displayed on the AIS screen. Common causes include blocked or damaged antennas, loose antenna cables, interference from shipborne electronic equipment, or failure of the positioning module.
Failure to Transmit/Receive Data: The AIS cannot broadcast its own information or receive information from other ships. The causes may include VHF antenna faults, channel congestion, incorrect communication parameter settings, or failure of the AIS communication module.
Abnormal Display or Garbled Code: The display screen has no image, blurred display, or garbled text. This is usually caused by damaged display screens, loose display cable connections, or faulty display drivers.
Frequent Alarms Without Reason: The AIS continuously issues alarms such as "collision risk" or "position deviation" when there is no actual risk. This is mostly due to incorrect alarm threshold settings, outdated software versions, or interference from external signals.
Quick Troubleshooting Steps
Onboard personnel can follow the "from simple to complex" principle to troubleshoot Class A AIS faults step by step:
Preliminary Inspection: First, check the power supply status (whether the power indicator is on), antenna connections (whether the antenna is loose, damaged, or blocked), and cable connections (whether the power cable, antenna cable, and display cable are firmly connected). At the same time, observe whether the AIS host has abnormal phenomena such as overheating, peculiar smell, or water ingress.
Restart the Equipment: For most minor faults (such as temporary signal interference, software crashes), restarting the Class A AIS can resolve the problem. Turn off the main power and emergency power, wait for 3-5 minutes, then turn on the power again and observe whether the equipment operates normally.
Parameter Check: If restarting is ineffective, check the AIS parameters, including communication channels (whether they are set to the standard VHF channels 161.975 MHz and 162.025 MHz), positioning system settings (whether multi-constellation positioning is enabled), and alarm thresholds (whether they are set reasonably according to the navigation environment).
Component Replacement Test: If the above steps are ineffective, use spare parts (such as spare antennas, power cables) to replace the suspected faulty components one by one. For example, if there is a positioning failure, replace the antenna with a spare one to check whether the problem is resolved.
Contact Technical Support: If the fault cannot be resolved through the above steps (such as internal component failure of the host), immediately contact the AIS manufacturer's technical support team or the nearest maritime technical service station, and provide detailed fault information (fault phenomenon, occurrence time, navigation environment) to obtain professional guidance.
Troubleshooting Precautions
When troubleshooting Class A AIS faults, onboard personnel must pay attention to the following points to avoid secondary damage:
Do not disassemble the AIS host without authorization, as this may damage internal components and void the product warranty;
When checking cables and antennas at heights, use safety protection equipment to prevent falls;
Record the fault phenomenon, troubleshooting process, and results in the navigation log for future reference and inspection;
If the AIS is out of service for a long time, report to the maritime authority in a timely manner and take alternative safety measures (such as strengthening visual observation and radar monitoring).
