Heading COG Mismatch (E125/ACU400/EV-1/P70/I70)

[lwitty]

Okay, I performed the following today:
1) Upgraded EV-1 software successfully
2) Upgraded the RS130 software successfully
3) Verified the ACU-400 SeaTalk power switch is off
4) Verified EV-1 arrow is pointing towards the bow. EV-1 is installed on the centerline of the boat behind the keel and at least 3 feet from any metal objects, compasses and radios.
5) Reset the pilot to factory settings then performed dockside wizard.

I then performed a sea trial with the following actions/results:
1) Completed multiple turns to allow compass calibration to complete. Completed with a variation of 10 degrees.
2) Verified the AP was holding course in Auto and Wind Vane mode - operated as expected.
3) All seemed fine for the first hour, however when heading back to the dock with the AP engaged on a fixed heading, the MDF seemed to go askew again - please see the attached photos. Here are the anomalies represented in the 2 photos taken within seconds of each other:
a) The chart is configured to be in Headsup mode with a 2/3 offset, so given the boat was going 7.7 knots on a fixed heading, the boat symbol should have been in the lower 1/3 of the screen.
b) You can see the COG is 148 degrees true and the Heading is 137 degrees true. However, the chart is showing the heading vector (purple) pointing at an estimated 360 degrees while the COG vector is showing the correct 148 degrees.
c) Note the correct heading is being displayed on the I70, but not the chart on the E125 vector and boat symbol positioning.

Given the above description, plus the fact I was seeing these exact symptoms before I upgraded the S3/Fluxgate to the ACU/EV-1(which is one of the reasons why I decided to replace the fluxgate and then replace the old S3 & fluxgate with the ACU-400/EV-1), it seems the heading information is correct and not an issue with the EV-1.

Next trip out, I will configure the MDF to show both Heading and COG data to determine if the heading matches the Heading Vector.

Any other thoughts on the heading issue?

The second issue, depth, seemed to be much more stable this time out. Seemed very accurate while out motoring and sailing and I only saw it drop to 0 feet once while in 200 feet of water. Since the depth started acting up, I would see this behavior multiple times in one hour. However, when I returned to the dock, I noticed it was reading 0 feet again then jumped back to 5-6 feet and back to 0 feet several times within a few minutes.