Instrument Failure Help

[Marc14857]

We are 1 week into our trip in Maine and had some major instrument problems today. Raymarine System E 80 MFDs St 60 instruments. Leaving Portsmith today for Portland just outside of the harbor we lost GPS fix and received no AIS alarm. These are two independent systems with separate antenna that tie into the MFD. Attempted to reboot numerous times and sometimes I would get a GPS fix immediately but loose it after about 20 seconds. This happened numerous times and I decided to call the marina and head back in. I turned the boat around and on my way back in the GPS and AIS came up and stayed up. We turned around again and made it to Portland without any recoccurance. In parallel with this I noticed my wind instrument was reading very low and under certain conditions indicated negative wind speed. I did replace the GPS antenna battery about a year ago but I thought the battery was just to maintain the last known position and not sure it had any impact on what was happening.

Not sure how all these ate related. Wind and GPS get their 12v supply from an instrument circuit and the AIS gets its power supply from a different circuit.

I have ISailor on my IPAD as a backup but am very uncomfortable continuing this trip unless I figure out what was going on.

Any ideas or thinks I could test for would be greatly appreciated.

Marc

 

[Rick D]

Well, I guess the first thing to check for is a voltage drop, even if it was OK last time you checked. FWIW, I had that happen a couple of times off San Diego with war games going on. I don't think it had anything to do with my boat!

 

[LeoLambert310]

check the battery in the GPS, had the same problem no fix change battery all ok. Its a pain had to take the GPS unit apart just to change the battery.

 

[Bill Roosa]

GPS are very finicky pieces of gear. Ocean racers take upwards of 6 units and usually finish with one or none working.......Never go to sea with only one form of navigation information.
I'd seriously recommend you get some good paper charts and learn how to use them so when (not if) your GPS dies at a critical moment (Murphy will see to it that BTW) you will not be left in danger not knowing where you are. FWIW

 

[Marc14857]

I have paper charts and know how to use them. That is still no reason not to try and troubleshoot the electronics and be able to use them as it is certainly more convenient.


I did replace the battery on the antenna last year.

Going to check voltage at the supply as that seems to be a common component.

Anything else to condider?

Rick D....The thought did cross my mind with the navy base there but probably not likely.

 

[SycloneDriver]

Check the ground (-) connection.

 

[Rick486]

Call Raymarine support. Have had very good luck with them in the past.

 

[DougM]

I don't believe the gps battery has anything to do with the problem.
You indicated that AIS and wind instrument were also flaky. I would look for a loose or corroded connection either on the power side or the ground side all the way back through the fuses to the circuit breakers.
The power for the MFD should be independent of the supply for the other instruments, so its either one or the other.
Hopefullythe E80 is not deciding to pack it in.

 

[Marc14857]

If it's the E80 I think i might be able to swap out the unit at the NAV station which is the Master with the unit at the helm which has always been in the slave mode. Not sure how much work that is but might be an option.

 

[Rick486]

When you were losing GPS posit, did you notice that shown on both MFDs? If both were showing loss of GPS I don't see how one MFD or connections to one MFD could cause that presentation. Also the wind instrument acting strangely. Was that concurrent with the GPS problem or separate? Lack of AIS alarm may be in the software such that with no GPS posit the navigation software doesn't know where the boat is hence affecting the AIS processing. When you lost GPS posit was the display still presenting the geographic picture? It's also possible that loss of the GPS could indirectly affect the wind instrument if you were displaying apparent wind and the processing was using own ship speed over the ground to calculate apparent wind. To me it really does sound like a GPS issue. Might be a good place to begin looking for bad connections. My GPS antenna is mounted in the deck on the starboard side. Is yours there? Is anything obstructing it's look?
Just my thoughts.

 

[Rick486]

Have a look at this.
https://www.winnipesaukee.com/forums/showthread.php?t=19281

 

[Bill Roosa]

well if you are running two GPS on the same buss that WILL cause problems. Only one instrument of each type is allowed on the buss. The MFD and the other GPS have to be set to be primary and secondary/alternate so they don't send two sets of data and confuse the other instruments. Try just turning one off and see if the other comes back on line.

 

[Marc14857]

When I lost GPS both units showed the boat initially on the middle of a land mass followed by no GPS and no AIS. The unit at the Nav Station is set as the Master and I believe the unit at the helm is merely a repeater. (That is if I understand it correctly). I did check voltages from wind transducer per raymsrine FAQ and all are in spec. We are at the dock in Portland and all seems to be working well for now. Going to marine store to get a 12volt socket to wire in st the helm so I will have a continuous source of power to run my IPAD (ISailor) app if necessary

 

[jssailem]

iSailor to the rescue. But it is a bit of a concern when the app opens and asks you to confirm be for access.....

THIS APPLICATION IS ONLY A NAVIGATIONAL AID AND IS NOT A SUBSTITUTE FOR ANY NAVIGATIONAL EQUIPMENT THAT MAY BE REQUIRED APPLICABLE REGULATION OR LAW.​