No temperature indication



NavNet VX2 and 235DHT-LMSE transducer. Just got the boat and found someone cut the 7 pin connector off the transducer cable. Oddly the spliced wires are not color matched. Transducer white connects to a white wire (okay that matches),transducer blue connects to a brown wire, transducer red connects to red, transducer black connects to a grey wire and the transducer bare connects to yellow wire. Any idea if this is correct? I guess the transducer was changed. Thank you and have a good evening.

No, that doesn't appear to be correct. What data port is the transducer being wired to?
It's difficult to tell because the cable gets lost in a wall. It is either data port 2 or 3. Should I open the wall? Further investigation reveals a in- hull transducer 527ID. I'm thinking the previous owner used the 527ID for depth and wanted the 235DHT-LMSE transducer for temperature only. How should the 235DHT-LMSE transducer be wired for temperature only? It is the same part number cable at data port 2 and 3. Assuming one is spliced to the 235DHT-LMSE transducer what colors would be correct for the splice? I thought the transducer had to go to a sonar module then to the MFD? Thanks for your help.

The 235DHT-LMSE is a smart sensor, it is not a fish finder transducer. It comes with a Furuno 7-pin NMEA0183 cable connector that can go to a NN2 10.4" display's data1 or data4 (if adapter cable is used); if a 7" NN2, then it would go to data1 or data3 (if adapter cable is used). If the sensor's cable has been cut it can go to any port other than data3 (10.4") or data2 (7") because that's reserved for heading only. The sensor's white (TX+) and blue (TX-) would connect to the yellow (RX+) and green (RX-) of the NN2 cable respectively; also to power the sensor, the sensor wires red (12Vdc) and black (power gnd) would be connected to a power source or breaker.

As for the 527ID-IHD, that is a fish finder transducer and should be connected to a network sounder first before interfacing with the NN2 system.


  • 235DHT-LMSE wiring diagram.pdf
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Thanks Reaper. I'll give another look as it definitely isn't wired per that color code. Actually I don't have a green wire unless it is faded or cut back and I didn't see it. If power and NMEA connections are corrected should I see temp on the VX2 MFD?

Another question. I observed and read today's tropical statement. The Rx signal was low. There are two weather sensors, Airmar PB100 and SRA-40. I don't know which one is connected to the serius weather computer BBWX1 as there is also a two port splitter not connected to the BBWX1. Which antenna is connected to the BBWX1. How do you improve reception or is the system operating correctly at Rx signal indication low? A piece of the plastic case on the PB100 and I'm unsure if it is affecting anything.
If you have your temperature source set to "NMEA" and a databox set up to display temp...then yes, you'll see temp on the NN2.

The SRA40 is the antenna connected to the BBWX1. Improving the signal strength depends...normally just ensure the antenna is installed with clear, 360 degree view of the sky.

The PB100 is a smart sensor that comes with a 7-pin NMEA connector on it. Normally goes to data1 or data4 with an adapter...or to an RD30 display.