Lewmar Bow Thruster Troubleshooting

[SeaSail]

Hello all,
I want to share a recent event with my Lewmar 185 tunnel thruster on my boat. In my last docking, the Lewmar control unit LED lights were on and the thruster was working well. However, in finishing docking, a thrust command caused the unit to trip off (LEDs out, no function). Any restarting the thruster controller (lights on) and subsequent thrust command caused the unit to trip.
In consulting our Forum, my thought was that the controller had gone south on me. I did find a valuable troubleshooting guide on the Lewmar site that was of great help in diagnosing the problem: https://www.lewmar.com/sites/default...m%20solver.pdf

In my particular case, it was not the controller, nor motor, nor "black box"! In checking the 400 amp ANL fuse, the resistance across the fuse was approximately 5 Meg-ohms - not open, nor fully conductive. Can a fuse be partially pregnant? In this case, yes. Removing the fuse from the holder, I found corrosion on the load side blade. Applying emory cloth, I soon had a zero resistance fuse and a working bow thruster. Just wanted to share one easy thing to check before buying replacement parts!

Cheers!