[CA] [CA11] No drive detected

[sgostling]

My autopilot has been working fine since I bought the boat 18 months ago, but now when I select the 'auto' button I get the alarm message 'no drive detected'

I have the following components
P70 software version 3.0.7
EV-1 software version 2.18
ACU 400 software version unknown although I did update about a year ago

The ACU400 no longer appears in the devices list when I display diagnostics although the device does have power (2 LED's one red, one orange(12V) are on)

I have checked and reconnected SeaTalk connections but still the same alert.

Any suggestions for what to try next would be greatly appreciated.

[Chuck - Raymarine - Moderator]

Welcome to the Raymarine Forum Steve,

The reported symptom may be indicative of poor autopilot drive unit motor and/or clutch lead connections to the ACU, a failure of the drive unit, or a failure of the ACU (either in its SeaTalkng / NMEA 2000 communications circuitry or within its circuitry responsible for powering the drive unit). I would be recommended that the diagnostics features Data Master MFD's or that of the autopilot control head be used to verify communications with the ACU. Should no communications with the ACU be verified, then it would be recommended that its SeaTalkng / NMEA 2000 plug be disconnected from the ACU and from the backbone's spur socket, that it then be reconnected, and that the test be performed again. Should the problem persist, then it would be recommended that the spur socket to which the ACU is presently interfaced by tested by connecting another one of the system's devices to that spur socket to verify the operational state of that portion of the backbone. Should the interfaced device communicate with the system's other devices, then it would indicate a problem with the ACU necessitating that it be sent to Raymarine’s Product Repair Center to be bench checked / serviced. Should communications between the ACU be verified, then it would be recommended that the drive unit's power and clutch (if any) leads be disconnected and then reconnected to corresponding terminals of the ACU to ensure that they are tight. Should the problem persist thereafter, then it would be recommended that the autopilot drive unit be tested. Should no fault be found with the autopilot drive unit, then it would be recommended that the ACU be sent to Raymarine’s Product Repair Center to be bench checked / serviced.

[sgostling]

Chuck,
I briefly checked the leads and everything looked tight, although I have a mechanic coming out tomorrow that can fully disconnect and reconnect them.

If the problem was the autopilot drive rather than the ACU would the ACU show in the list of devices on the MFD?

[Chuck - Raymarine - Moderator]

Steve,

Q. If the problem was the autopilot drive rather than the ACU would the ACU show in the list of devices on the MFD?
A. Negative. The MFD's devices list would only list those devices which had been directly interfaced to the MFD via Ethernet or SeaTalkng / NMEA 2000 communications. As drive units and rudder reference transducers are designed to be interfaced to the ACU rather than the SeaTalkng / NMEA 2000 backbone, these devices will not be listed.