Furuno FCV-628 and Furuno 525STID-MSD

My Raymarine fish finder was beginning to fail, loosing bottom at 200'. It was either the unit or the transducer. Initially I installed the Furuno FCV-628 and hooked up the existing transducer. It became clear the transducer was on its way out. I pulled the boat out of the water and installed a new Furuno 525STID-MSD Transducer. This is a triducer, with speed through water and temperature in addition to depth. An extension cable was needed to complete the install. All transducer parts and extension cable made by Airmar. The transducer fit in with the existing hole and faring, which was a good thing.

I'm now trouble shooting the temperature function of these units. I am getting a strong bottom signal so that is fine and a big inprovement on the old transducer. The boat is at the dock so have not checked speed yet. I am unable get temperature I phoned Furuno and spent a considerable time with Furuno working through the menus and checking functionality. The tech thought the transducer was the issue, so I phoned Tech support at Airmar. The tech walked me through checking impedance on the transducer cable at 4 pin and 7 pin. I got 18.35 K Ohms, which is consistent with 53 degrees F, and that is probably the proper water temperature. I also checked this at end of the extension cable and got a similar value, so the extension cable checked out. The Airmar Technician suspects the Furuno 628 and suggests a definitive test of putting a 10,000 Ohm resistor across pins 4 and 7, which should register a temperature on the Furuno unit of 77 F.

I am going to search out this resistor, but post here as an update to my progress this far. If anyone has any experience with working through this, I am all ears (and eyes).

Jim

It sounds like you drew the short straw on odd problems. Glad you are around, because I usually get that straw But it sounds like you are doing the right things to trouble shoot the issue.


A few random thoughts:


- As I recall, them temp is displayed as some combination of a graph line on the ticker-tape bottom display, and a numeric value. Is anything visible and there is just a wacky value, or does it appear the device isn't even trying to display temp, which would suggest is things the info isn't present at all. The later is likely equivalent to the temp signal being open circuit (not connected).


- I think the Airmar guy's suggestion is a good one, and should clearly indicate whether the FCV is seeing any signal. Don't feel you need a exactly 10k ohm resistor. If 18K equated to 53F, then anything in the 5-30k range should do the trick.


- Did you old Ray setup have temp? If so, it might shed some light to apply the temp signal from the new transducer to the old display, and the only transducer to the new display, just to see if the temp problem follows the display or the transducer.


- If there was any way to borrow another transducer, you could plug that directly into the FCV to see if you get temp. There should be no need for it to be in the water for that to work. Or worst case, you could hang it over the side of the boat. If you are friendly with a local electronics shop, they might have something kicking around.


- And just to confirm the cabling, the transducer has an integral cable with 10-pin connector. Then you have a Furuno 10-pin extension cable. And the extension cable plugs directly into the FCV

twistedtree said:

It sounds like you drew the short straw on odd problems. Glad you are around, because I usually get that straw But it sounds like you are doing the right things to trouble shoot the issue.


A few random thoughts:


- As I recall, them temp is displayed as some combination of a graph line on the ticker-tape bottom display, and a numeric value. Is anything visible and there is just a wacky value, or does it appear the device isn't even trying to display temp, which would suggest is things the info isn't present at all. The later is likely equivalent to the temp signal being open circuit (not connected).

Click to expand...

Thanks TT. I spent most of the time with Furuno getting the DATA1 and DATA2 displays working with the "Mode" nob. The Temperature readout only displays dashes ---.---

twistedtree said:

- I think the Airmar guy's suggestion is a good one, and should clearly indicate whether the FCV is seeing any signal. Don't feel you need a exactly 10k ohm resistor. If 18K equated to 53F, then anything in the 5-30k range should do the trick.

Click to expand...

Yes, I understood that as well.

twistedtree said:

- Did you old Ray setup have temp? If so, it might shed some light to apply the temp signal from the new transducer to the old display, and the only transducer to the new display, just to see if the temp problem follows the display or the transducer.

Click to expand...

It did but it never worked. It's a nine-pin setup and the existing cable cannot be plugged in. I could do some sort of splice but...

twistedtree said:

- If there was any way to borrow another transducer, you could plug that directly into the FCV to see if you get temp. There should be no need for it to be in the water for that to work. Or worst case, you could hang it over the side of the boat. If you are friendly with a local electronics shop, they might have something kicking around.

Click to expand...

I'm going to work with the resistor first and then see where it goes. I might see if I could borrow a 628 Unit from Western Marine. So long as I bring it back. We've ascertained that the transducer is viable, at least according to the test I did with the Airmar Tech. In the end, it might be a warrenty issue with the Furuno Unit.

twistedtree said:

- And just to confirm the cabling, the transducer has an integral cable with 10-pin connector. Then you have a Furuno 10-pin extension cable. And the extension cable plugs directly into the FCV

Click to expand...

Yes. That is correct. Everything 10-pin.

Yes, TT, I have had my trials with the breakdowns this summer. None of them have been easy paths.

One other note. This is the only nav device connected to the N2K and then to the Nemo Gateway. I wonder if there is some sort of conflict from that. I shall look into that possiblity. I can always move the data stream to the Gateway with the vacant Nema 0183 port.

Jim

JDCAVE said:

One other note. This is the only nav device connected to the N2K and then to the Nemo Gateway. I wonder if there is some sort of conflict from that. I shall look into that possiblity. I can always move the data stream to the Gateway with the vacant Nema 0183 port.

Jim

Click to expand...

How is it connected to N2K? It doesn't have a native N2K connection.


It would be odd, but disconnecting the 0183 data interface wouldn't hurt the try.


Just looking at the menus, I'm sure you tried this with Furuno, but just in case..


There is a menu selection under Data for Temp Source. That should be set to Own, not NMEA.

T.T. It goes through one of those N2K converters. It’s the only legacy equipment from the former PC navigation network from the PO. I went to a NUC and Nemo gateway, if you remember. The weather station and ES went through the N2K. As I mentioned there is on N0183 port remaining on the Nemo and I might use that.

Yes, I set the Temperature sensor to “own”.

JDCAVE said:

T.T. It goes through one of those N2K converters. It’s the only legacy equipment from the former PC navigation network from the PO. I went to a NUC and Nemo gateway, if you remember. The weather station and ES went through the N2K. As I mentioned there is on N0183 port remaining on the Nemo and I might use that.

Yes, I set the Temperature sensor to “own”.

Click to expand...

Got it, thanks. The "own" temps source did seem too obvious, but I had to ask.


It sure seems like a defective FCV at this point.

According to Airmar, putting this on 4 and 7 pins the unit should should display 54 degrees F.

Jim

I put the resistor across 4 and 7 pins. No resulting display on Temperature. I have a call in to Furuno.

I talked to both Furuno and Stryker Electronics in Port Hardy, from whom I purchased the unit. Stryker told me to send the unit to them and they will look after the warranty work and send me another unit.

Jim

I have water temperature! Finally! It should not have been this hard!

However major Kudos to both Furuno, Airmar and Stryker electronics for their support!

Photo to follow when I’m on wifi!

Bonus. I’ve got water temperature displaying on Coastal Explorer.

Jim

Great news Jim.

...and thanks for your help too, TT.



Jim.