お使いの機種名を選択して、この情報が該当するかどうか確認してください。

Lock to Lock test fails on the GHP 20 Marine Autopilot System with SmartPump

The GHP 20 Marine Autopilot System with SmartPump contains an automatic calibration procedure called the Lock-to-Lock test. This test allows the SmartPump to steer the engines or rudder fully to both port and starboard to learn the limitations of the hydraulic system.

If there is a problem in the hydraulic installation, this test is unable to complete properly. A "Lock to Lock Failed" message will show on the GHC screen. This failure can be caused by multiple issues.

Issue 1 - Power

The most common issue that causes this failure is inappropriate power being supplied to the ECU. Inspect the connection between the ECU and the battery to make sure that the power and ground connections are secure. If an extension was used on the power cable, make sure the appropriate gauge of wire is used. The proper gauge of wire can be determined based on the length of the extension. Specifications for the proper gauge of wire can be found on Page 14 of the Installation Instructions.

If the power connections from the ECU are connected to a breaker bar or fuse panel, please disconnect them. Instead, connect the red and black wire from the ECU directly to the battery.

Issue 2 - Shadow Drive

An improperly installed Shadow Drive can also cause the lock-to-lock failure. Please review the Installation Instructions that came with the GHP 20 for proper installation procedures. Instructions for properly mounting and installing the Shadow Drive start on Page 2.

If the Shadow Drive is installed properly, but the Lock to Lock test continues to fail, it may be necessary to disable the Shadow Drive for the duration of the autopilot setup*. Please follow these steps to disable the Shadow Drive:

  1. Start from the Heading screen on the GHC
  2. Select Menu
  3. Select Setup
  4. Select User Autopilot Configuration
  5. Select Shadow Drive
  6. Select Disable

After the Shadow Drive is disabled, the setup Wizards can be accessed through the Dealer Autopilot Configuration menu.

*Please note that while the Shadow Drive is enabled, the GHP 20 Autopilot will continue to try to control the boat until the Standby button is pressed. The Shadow Drive must be enabled using the process listed above upon completion of the Autopilot setup.

Issue 3 - Air in the hydraulic lines

This failure can also be caused by air being present in the hydraulic hoses after installation. Any air that has not been properly bled out of the hoses can cause multiple steering issues on the vessel. Review the bleeding instructions for the hydraulic steering system installed on the vessel to make sure the proper process is being used.

The GHP 20 can be used to determine if there is air in the hydraulic hoses. Please follow these steps to test for air in the lines:

  1. Disable the Shadow Drive using the steps listed under Issue 2 above
  2. Press Back until the Heading screen shows
  3. Press Menu
  4. Select Setup
  5. Select Dealer Autopilot Configuration**
  6. Select Speed Source Setup
  7. Select Speed Source
  8. Select None
  9. Press Back three times
  10. Select Steering Mode
  11. Press Select until Rudder steering mode is shown
  12. Press Back two times
  13. Press Engage to engage the autopilot
  14. Press and Hold down one of the direction arrows. Continue to hold down the arrow even after the engines are hard over

If the hydraulic hoses are installed properly, the GHC 10 will display a Pump Stall Error shortly after the engines have reached the stops. When this message shows, release the arrow. If the Pump Stall Error never shows, that indicates that there is air in the hydraulic hoses, and the system needs to be bled again.

After completing this test, be certain to set the Speed Source back to the appropriate selection for your installation.

**After the initial installation, the Dealer Autopilot Configuration menu no longer appears in the menu. If needed, please contact Garmin Support for instructions on how to access the Dealer Autopilot Configuration again.

If the autopilot continues to fail the Lock to Lock test after following the above tests, please contact Garmin Support.