[TG] Zero Depth readings

[Bob234]

Hi,
I have an a120 MFD and 4 x i70s instrument heads running successfully since installation in April 2017. Recently I have been getting false depth readings flickering down to zero and staying there for a while (30 seconds or so) then returning to expected readings. This is replicated on the MFD. This has been happening in open water (3 to 30 metres) when there is no turbulence from passing traffic.
I see from the forum there isn’t a check I can perform on the depth transducer other than running an independent transducer as a comparison.
After consulting the forum for similar problems I have unplugged the clear cable from the depth transducer in the itc5 (as suggested to someone else) in case I have interference. I am waiting to test the effectiveness of this on a longer run.

This morning after switching on the instruments I had 3 dashes for depth, speed, wind speed, and no wind indictator arrow, the only readings I had were cog and sog from the gps. After about 5 minutes I motored for a couple of minutes to a mooring and the readings came back up.
I have done a check again since and the instruments are all reading again soon after turning the system on.

So, at the moment I have all readings available, the depth is showing as anticipated subject to a longer test for the depth. However, given the 3 dashes readings this morning I am beginning to suspect an intermittent problem with the ITC5.

Apart from sending back the itc5 for testing (which would be very limiting as we live aboard) do you have any suggestions?

We are currently in Long Island Sound.

Many thanks.

Bob