Temperature stopped displaying on FCV585

Question

​I have an FCV585 Fish Finder with an Airmar 260 transducer.  The temperature graph has always worked in the past, but will not display now.  It is set to on, but no temp line or temp scale displays on the screen.  Any suggestions on what the problem may be and how to remedy?

Solution

First, check to see if the temperature will show up in the data box. You can do this by turning on a data box and select temp for the data from the menu. If you still don't have a temp indication, then the problem could be either the display or the transducer. The easiest way to check the temp is to half split the system. Connect up a known good transducer and see if you have temp. If you don't, then the problem is the display. Another way to check the system is to check the resistance of the temp sensor. If you connect an Ohmmeter across pins 4 and 7 of the transducer connector you will get around 10k ohm if the temp is around 70° F. The resistance will vary slightly with the temp. You should not get an open or a short. 

If you do not get 10k ohm, then it is likely that the transducer needs to be replace. If you are getting 10k ohm, it is likely that the temperature sensor in the unit needs to be fixed. You will want to have your authorized dealer look at it, or you can send it in to our repair facility at the address below. If you send it in, please make sure to include a description of what is happening. 

Furuno USA, Inc.
Repair Department
4400 NW Pacific Rim Blvd.
Camas, WA 98607