FCV800 Depth Reading Issue

[buefin039]

I have an FCV800 and it is having a very strange depth reading issue. I will be on level seafloor and it will adjust the bottom down and up and make it look like I am going over changing depths. The redline at the top of the screen will start to get thicker for no reason and as this happens that bottom pushes down and I start to read deeper. If I am in 20' and the surface redline grows to 10' then my depth reads 30' and the screen bottom looks like it is getting deeper. I have seen it go the other way where the line at the top goes up then disappears and my depth reads shallower until it comes back into view again. It has this issue at all depths but is most noticeable in shallow.

Here are the specs and what we have tried.

XDR port 1 : CW 525T-LTD/20 B60 LH
XDR port 2 : B175M Chirp

I updated the FCV800 to the latest software with no change
Factory resets with no change
Reset machine to just CW ducer (unplugged chirp) and it did it. Reset machine to just Chirp ducer and it did it.
TDT test the transducers and both in spec.

It acts as though the machine is constantly self adjusting the transducer depth offset up and down. When testing I do not change boat speed so the transducer will stay at same depth in water.

Please see attached screen shots where I was just going along in a steady depth around 9'. Besides this issue the machine marks beautifully and has been very impressive.

 

[Johnny Electron]

That is odd. What version of software is in the machine? 2.06 came out in June and it might be worth a try starting there.
No one has painted the transducers have they?

 

[Johnny Electron]

@Deep Blue

 

[buefin039]

I upgraded to 2.06 as soon as it was available and it did not change anything. Both transducers have prop-speed foulfree on them.

Here is a screenshot of self test page.

 

[buefin039]

Today I docked in a deep water slip and figured I would go through all the settings until it stopped.

It ended up being that the heave compensation was turned on and you cannot see that until you enter that menu. Turned it off and it is working perfectly. The machine marks fish awesome with either transducer and we are holding bottom well to about 34 knots or so. Great machine.

If heave compensation is on the factory resets were not clearing that I guess.

 

[Johnny Electron]

That shouldn't default to ON even when resetting. Glad you got it figured out.