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Humminbird 999ci HD SI Review

Humminbird 999ci HD SI has an average rating of 2.18 out of 5 based on 11 user reviews.



The fully waterproof Humminbird 999ci HD SI Combo sonar fish finder has a wide variety of features for finding fish in multiple locations. The screen is eight inches wide, and consists of a 480V x 800H pixel high definition full-color LED display that is in a 16:9 ratio. Side Imaging Sonar and Down Imaging Sonar allow for clear images of structure and fish, and also give coverage of a 240 foot section that can be seen from either side of a boat, for a total of 480 feet from side to side, along with the downward two dimensional high frequency sonar capabilities to identify structures and fish that are beneath the boat. The DualBeam PLUS sonar puts out up to a maximum of 8000 Watts of PTP power with options to view the beams side by side, blended, or separately. A 60° beam gives large fish coverage, and can locate fish on the bottom with high detail. SwitchFire Sonar is capable of targeting fish to a depth of 1,500 feet and it includes max mode, clear mode with Time Variable Gain (TVG) software, and three color palettes to handle all conditions of light exposure.

The internal color GPS system has a 50 channel receiver, and offers ContourXD mapping for chart plotting and advanced capabilities that allow for marking locations directly on the screen. As many as 2,500 points and 45 routes can be programmed into the GPS. GPS and sonar data can be shared between two units by using the Ethernet port, and are compatible with 360° imaging and trolling systems. The pre-loaded ContourXD maps include more than 3,0000 United States Lake locations and major ports, roads, interstates, and markers and also give location for drops and channels.

Also included are dual SD card slots, True Arch Technology, instant image update, sonar recording, GPS speed, and selective fish ID+. Display color can be selected, and with the optional 200/50 kHz transducer the depth capability increases to 3,000 feet. The transducer is included with a transom mounting type and temperature. Additional features include recording split screen, snap shop onto the memory card, bottom lock, and a unit cover. You can get a great deal on Humminbird 999ci HD SI here.

 Lowrance HDS-7 Touch InsightHumminbird 999ci HD SIGarmin GPSMAP 840xs
Screen Size7 in8 in8 in
Screen Resolution480 x 800 pixels480 x 800 pixels600 x 800 pixels
Display TypeWidescreen, 16:9 ; WVGA color TFT LCD16:9 Colorcolor SVGA
Imaging2D, DownScan, StructureScan, Downscan Overlay2D, Down Imaging, Side Imaging2D, Down Imaging (Side Imaging available with GVC box sold separately)
Transducer TypeTransom Mount/Trolling MotorTransom Mount/Trolling MotorTransom Mount/Trolling Motor
Transmit Power31W Broadband RMS (analog equivalent 3200W)
250W Broadband Peak-to-Peak (analog equivalent 30,000W)
1000W RMS
8000W Peak-to-Peak
1 kW traditional
Sonar Frequency(50/200 or 83/200 kHz) + 455/800 kHz83/200 kHz 2D
455/800 kHz Side Imaging
77/200 kHz 2D
Also supports 50/200 dual frequency transducers
Maximum Depth5000 ft / 1524 m1500 ft 2D
150 ft Side Imaging
1,750 ft @ 50 kHz, saltwater, Garmin dual freq transducer @ 500 W

2,700 ft @ 50 kHz, saltwater, Airmar B260 transducer @ 1000 W
GPS Antenna TypeInternal, high-sensitivity GPS+WAASInternalInternal
Waypoint Storage50003000500
Plot Trails10 tracks, 12,000 points50 tracks, 20,000 points50 tracks, 50,000 points
Default MapsExpanded U.S. BaseMap or Insight USAHumminbird ContourXDU.S. LakeVu and BlueChart g2 coastal maps

User Reviews

Posted by Mike from KY

  • 1/5

I bought this 4 months ago and I had problems with it from the beginning. When I go to the DI mode the display shows white horizontal lines. I’ve been on the phone with Humminbird support several times. We went through my installation, they concluded the installation was correct. They recommended software updates, I upgraded software 3 times already, white lines are still there. I sent the display unit to Humminbird, they sent it back saying there is no problem with the unit, it’s a known software bug. So what this comes down to is I paid $1500 for the fishfinder, $40 for shipping and insurance and I have a unit that doesn’t work. Thanks a bunch, Humminbird.

Posted by Steve

  • 5/5

My new 999 has been fantastic. The clarity of the side imaging and down imaging is really cool and the unit is able to solidly track bottom at full speed (I’ve had other older units that lost bottom just after getting on plane). The side imaging has helped identify fish-holding structure and fish, on occasion. Installation was pretty much the same as any other unit.

Posted by Dale

  • 2/5

Purchased this unit and after no even three hours the screen locked up. Turned unit off for a few minutes and nothing but the control button lights would come on. After returning home the next day I hit the power button and it came on. The following week we go take out the boat and turn the unit on and it locked up again after a hour or so. Called hummingbird support for them too just say I don’t know . Lol
I think I should have went with a different brand.

Posted by Toby

  • 5/5

I purchased the Humminbird 999ci hd combo and I have to tell you I couldn’t be happier. First time out using the side image we located school of fish, marked them and then jigged catching a ton of yellow bass. Since learning the system I have fished areas I never would have fished before and have regained the fun in fishing. My son had lost interest in fishing prior to this finder and now bugs me every week to go back out and fish.

Posted by Todd D.

  • 1/5

I have 998 HD installed on my dash and I wanted get another one for the front of the boat. I was told 998 has been discontinued and I should buy 999 which is what I did. The new unit is not an improvement over the old one, in fact it’s much worse. 998 has a much better target resolution and seems to be way more sensitive. I’m a longtime Humminbird user and so far I have been very happy with their units but 999SI is an inferior unit.

Posted by larry

  • 1/5

@Mike from KY
My unit is doing the same thing,in DI white lines, when I have the chart speed set to TWO… If you run the chart speed and don’t use 2 then mine is okay other than other issues I am having. What is strange is Humminbird has know about these issues for a long time and no fix as of now…
To me it is false advertisement, maybe one day we can all get together an place a class action suit against Humminbird.
I wish they would fix the problems or take back the units.

Posted by Allen from Alabama

  • 5/5

I got this unit with my new boat, dealer installed, have had no problems with it at all. Others have had problems, I think it not been installed right, or they just have not done the updates as requested to do at start up. This thing is awesome getting another one for the bow and network. Excellent unit!

Posted by Mike

  • 1/5

Not happy, first no mapping at coast line. Second loses bottom at speeds over 15 mph. Third has lots of features and screens but only 3 presets. I won’t buy another Humminbird product. Maybe it works better on a slow rowboat. Yeah yeah I hear it may be installed incorrect. Easy way to blame user. Not product.

Posted by Tim

  • 1/5

I wished I had done more research, bought my 999 worked great for a while now when powering up the buttons will illuminate but screen will not power on up and the unit will not power down without unplugging. Humminbird wants an arm and leg to repair unit since unit is out of warranty. NOT HAPPY

Posted by Will

  • 1/5

This unit doesn’t even compare to my Lowrance unit!! Depth bounces all over the place and the unit now went black and won’t come back on only buttons light up like the other complaints I will never purchase a humminbird unit again!! Thanks for a 1500 dollar mistake!!

Posted by dan

  • 1/5

Unit got caught in rain storm with cover on graph and slightly tilted forward, Rain leaked in thru sd card slots and filled inside of graph. wrecked graph. water proof my butt! got to use it 1/2 season for 1,400.00 bucks JUNK!!!

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