GT15M-TH Transducer
Installation Instructions
Important Safety Information
WARNING
See the
Important Safety and Product Information
guide in the
chartplotter or fishfinder product box for product warnings and
other important information.
The device must be installed with at least one of the included
anti-rotation bolts. Failure to do so could result in the device
rotating while the boat is moving and could cause damage to
your vessel.
You are responsible for the safe and prudent operation of your
vessel. Sonar is a tool that enhances your awareness of the
water beneath your boat. It does not relieve you of the
responsibility of observing the water around your boat as you
navigate.
CAUTION
Failure to install and maintain this equipment in accordance with
these instructions could result in damage or injury.
Always wear safety goggles, ear protection, and a dust mask
when drilling, cutting, or sanding.
NOTICE
When drilling or cutting, always check what is on the opposite
side of the surface.
To obtain the best performance and to avoid damage to your
boat, you must install the Garmin
®
device according to these
instructions.
Read all installation instructions before proceeding with the
installation. If you experience difficulty during the installation,
contact Garmin Product Support.
Registering Your Device
Help us better support you by completing our online registration
today.
• Go to
• Keep the original sales receipt, or a photocopy, in a safe
place.
Software Update
You may need to update the device software when you install
the device or add an accessory to the device.
This device supports up to a 32 GB memory card, formatted to
FAT32.
Loading the New Software on a Memory Card
You must copy the software update to a memory card using a
computer that is running Windows
®
software.
NOTE:
You can contact Garmin customer support to order a
preloaded software update card if you do not have a computer
with Windows software.
1
Insert a memory card into the card slot on the computer.
2
garmin.com/support/software/marine.html
3
Select
Download
next to the software bundle that
corresponds with your chartplotter.
NOTE:
The software download includes updates for all
devices connected to the chartplotter. Select the correct
bundle that corresponds to the chartplotter to be updated.
You can select See All Devices in this Bundle to confirm the
devices included in your download.
4
Read and agree to the terms.
5
Select
Download
.
6
If necessary, select
Run
.
7
If necessary, select the drive associated with the memory
card, and select
Next
>
Finish
.
8
Extract the files to the memory card.
NOTE:
The software update can take several minutes to load
onto the memory card.
Updating the Device Software
Before you can update the software, you must obtain a
software-update memory card or load the latest software onto a
memory card.
1
Turn on the chartplotter.
2
After the home screen appears, insert the memory card into
the card slot.
NOTE:
In order for the software update instructions to
appear, the device must be fully booted before the card is
inserted.
3
Follow the on-screen instructions.
4
Wait several minutes while the software update process
completes.
5
When prompted, leave the memory card in place and restart
the chartplotter manually.
6
Remove the memory card.
NOTE:
If the memory card is removed before the device
restarts fully, the software update is not complete.
Mounting Considerations
• On a boat with more than a 5° deadrise angle, a fairing block
will need to be fabricated (not available for sale).
• On a boat with a 12° deadrise angle, the transducer with a
fairing block can accommodate a hull up to 29 mm (1.15 in.)
thick.
• On a boat with a 20° deadrise angle, the transducer with a
fairing block can accommodate a hull up to 19 mm (
3
/
4
in.)
thick.
• On displacement hull vessels, the transducer should be
mounted near the centerline.
• On planing hull vessels, the transducer should be mounted
aft, on or near the centerline, inboard of the first set of lifting
strakes.
• On displacement hull and planing hull vessels, the transducer
should be mounted on the starboard side of the hull where
the propeller blades are moving downward.
• On stepped hull vessels, the transducer should be mounted
directly in front of the first step.
April 2017
190-02161-02_ 0B
