ST40 / Airmar Speed Transducer Not Working

[SolNola]

I have a bit of a strange problem with my new (to me) boat's speed transducer. The temperature and depth readouts work just fine, but the speed always reads 0.00 knots.

I assumed it was fouled, so yesterday I removed and cleaned the paddle wheel. I was surprised that it wasn't very dirty. The paddle wheel spun freely, and I tried to test it by spinning and watching the readout, but it still displayed 0.00.

My next idea was to check the electrical connections, but I was disappointed to find that one of the prior owners installed the ST40 bidata display in a way that's nearly impossible to service. The back side of the panel is blocked by the installation of an aftermarket wall that covers an A/C unit (and possibly the A/C unit itself blocks access).

I thought I would reach out and see if anyone has experience with continuity / electrical problems with airman paddle wheels on ST40 displays. I thought it would read -.-- or something along those lines if there wasn't a signal.

Is it likely that the transducer itself failed (while still able to spin freely)? Can it be replaced by splicing a new unit into the existing wire?

Thanks for the help!

[GordMay]

Greetings and welcome aboard the CF, SolNola.

Go to ➥ http://www.cruisersforum.com/forums/...ent-15440.html

[SolNola]

Originally Posted by GordMay

Greetings and welcome aboard the CF, SolNola.

Go to ➥ http://www.cruisersforum.com/forums/...ent-15440.html

Interesting. Thanks for the write up. Do you know if there's a way to remove the ST40 instrument without access to the rear?

[lockie]

Originally Posted by GordMay

Greetings and welcome aboard the CF, SolNola.

Go to ➥ https://www.cruisersforum.com/forums...ent-15440.html

Yes, check out this thread for my recent post for more info.