Thread: Problems With Humminbird 788ci

The last 3 times out my unit has started to lock up all of a sudden on 1.2'. Everything else on the unit works fine, this may last 2 min or 15 min. I've turned of the unit and restarted but it still shows 1.2', I've even pulled the transducer out of the water, it's on the trolling motor and it still reads the same depth while it's laying flat on the boat. I called Humminbird yesterday but the tech guy didn't really have any idea. I'm hoping someone on hear might have an idea, my wife just thinks I'm having problems so I can get a new DI unit Doh Any help would be appreciated.

I really like the product but this is the second unit I've had problems with. Had a 565 that would stay fogged up for have the morning so you couldn't read it and now this. This unit is 2yrs old but until 6 months ago I was using the transducer from the 565 (they're the same) so the transducer I'm using is only six months old.

Originally Posted by Blackhawk19

The last 3 times out my unit has started to lock up all of a sudden on 1.2'. Everything else on the unit works fine, this may last 2 min or 15 min. I've turned of the unit and restarted but it still shows 1.2', I've even pulled the transducer out of the water, it's on the trolling motor and it still reads the same depth while it's laying flat on the boat. I called Humminbird yesterday but the tech guy didn't really have any idea. I'm hoping someone on hear might have an idea, my wife just thinks I'm having problems so I can get a new DI unit Doh Any help would be appreciated.

If the "surface clutter" is set at the default which is 5, try the 3 setting..You have to be in the "advanced menu" mode.

Thanks, I'll try that. I won't get to go again till the end of next week, I'll let you know if it works.

I also should have said that after it locks up it will go to working again and then lock up again.

Are you in shallow water say 10 ft ish. IF so you can try to set a max depth versus using automatic. That has been known to help with shallow depth readings.

Yes, I was in water about 6' deep and had the depth setting on 10'. I'll try that.

Blackhawk19,

Are you running a second sonar unit? If so, try turning it off to see if that helps or not.

Have you updated the software in your 788ci unit? The current available version is 5.400 but if you wait a few days the newer 5.840 version may be available – I am pretty sure that the 5.840 version should have changes in it for shallow water readings.

If you can; test your 788ci unit on someone else’s boat that is running a Humminbird unit. Except for the 3D and new DI models; any other model of Humminbird unit will work for this test (even the Side Imaging units); just be sure to connect only the power and transducer cables for this test. I am trying to rule out your transducer and anything else on your boat as being the cause of this.

Try setting the Surface Clutter menu to a lower numerical setting (this will decrease the amount of surface clutter) as Don G stated but you may have to go as low as a setting of 1.

Try setting the Water Type menu to the “Salt (deep) menu setting. I know that this sounds weird but when you change this menu setting it changes some electrical filtering that the units do and it can help.

Greg I have not updated, I'll wait a few day for the new update. I'll try the other things you suggested but it will probably be week after next before I get a chance to get the boat wet. Have some honey do and 3 appointments at the Montgomery VA next week. Thank You for your response.

I wanted to say thanks for all the help and Greg when I loaded the newest update (584.0) it took care of all my problems.