SPX 30 Drive Stop Issue

[SVNeko]

Thanks, Chuck. The drive stop issue only happens intermittently, which makes diagnosis difficult. I do not think it is the drive, since the drive responds to direct power input consistently. I have had the ACU checked by Raymarine about a year ago and last week by a local Raymarine authorized tech. Both times it checked out as working properly. My question is whether it is likely that the ACU fails periodically, and if this can be checked. Also, which newer model would be helpful as a replacement.
Thanks,
Peter Malloy