FAP-330 Issues

[offshoretug]

On a 4,000 mile voyage and having auto pilot issues.

Vessel has an FAP-330 Auto Pilot/FAP-3302 Processor and an SC-50 Sat Compass.

We've had a sporadic issue with the Auto Pilot randomly going hard left then giving the E24 Alarm. The sporadic issue is now a constant issue; once auto pilot is activated, vessel goes hard left, then swings back to 25 deg stbd.

Heading on AP display is consistent and correct with SC-50, and adjusts to port as the vessel swings to port when AP is engaged.

This happens on both of the vessel's steering pumps, rudder angle indicator appears to be working and directional relays under the console operate as normal when head unit gives the order.

Power has been recycled for the Sat Compass and the Auto Pilot with no change.

No alarms listed in Sat Compass messages.

On Sat Compass, OTHERS menu, Hold HDG Data is ON, HDG Restoration is ON, and HDG Backup is set to 5 min.

Self Test on Auto Pilot has been performed as listed on page M-5 in the Operators Manual and all appears normal.

Any suggestions on further troubleshooting steps, or potential causes of this issue?

Thanks in advance.

 

[offshoretug]

The chief engineer identified the “left rudder” solenoid to be sticking. Relay was cleaned with emory cloth and is functioning as it should. Replacement relays have been ordered.

 

[Johnny Electron]

Yes, relays/solenoids are a wear out devices and a very high possibility.