2 GPS receivers required for one system, Yamaha and Garmin?

[barcodepesca]

Hi. I have a single 300hp 2020 Yam with CL5, bolt on DES and autopilot, joystick etc. I have 2 Garmin 8412 xsv MFD's with marine network between them and they are also each connected to a NEMA 2000 backbone. Installation is basically the same as the wiring diagram on P78 of https://www.yamaha-motor.eu/content/...CC_B2B_ENG.pdf (P78). This Yamaha system has a Garmin GPS 19x receiver connected to the bus of the Yamaha multihub etc harnesses, for use by the autopilot and GPS speed etc (J1939 connection I think?), P78 again.

The 2 Garmin MFD's, connected to the NEMA 2000 use a second GPS 19x that is connected to the NEMA 2000. So I have 2 identical (except one is J1939 and the other NEMA 2000) GPS receivers connected to one system. I have to shift the receivers off the top of the centre console to above the canopy to get better reception (drops out sometimes) so I would like to get back to 1 x GPS 24x (19x has been discontinued) for the whole system.

The MFD's are currently connected to the YAM multihub via J1939 from one MFD to the Yamaha multihub P140. Garmin state that the MFD cannot transmit over the J1939 (only receive) so this is why there are 2 GPS 19x, one for Garmin and one for Yamaha, I guess. I cannot see the engine GPS receiver listed on the Garmin MFD's.

However P141 (also attached) shows a 13 6YG-8A2D0-11-00 6YG Gate way to connect the Yam multihub to the NEMA 2000.

My question is, if I connect this gateway NEMA 2000 to the Yam multihub, will the YAM and YAM autopilot have full access to the one GPS 24x connected directly to the NEMA2000 backbone (and hence I can ditch the J1939 GPS19x J1939)?

Thank you in advance for a response.

[barcodepesca]

Documents referred to above

[fairdeal]

Very interesting.

Would you try an experiment?

- disconnect the NMEA 2000 cable from one of the Garmins
- take the cable that currently goes to the Garmin J1939 port -
(from the Yamaha hub)
and, instead plug it into the Garmin's NMEA 2000 port:

does the Garmin then 'see' the GPS 19x that is on the Yamaha hub?

if it does,
did you say you have both Garmins currently connected via J1939?

what do you get,
if you connect both of those "J1939" cables to just one of the Garmins -
one cable to the J1939, one to the NMEA 2000 port?

does that still give you the "Yamaha page"?
and the Yamaha's GPS 19x?

[barcodepesca]

Hi. One omission on my part. When the motor (YAM command link) is turned on, the YAM GPS receiver can be selected on the Garmin MFD with the J1939 link to the YAM multihub. The issue with this is when fishing, using the mini Kota to move around the reefs, the motor is off and I want the GPS to work. So the GPS receiver on the nema 2000 is a must. My question is how to get this one GPS receiver to be seen by the YAM command link and whether the 13 6YG-8A2D0-11-00 6YG Gate way to NEMA 2000 on the multihub will allow the Yam to use this one NEMA2000 GPS receiver. I ca see some logic in having 2 so that each has its own independent receiver regardless if the other system is running or not. However the MFD and NEMA 2000 will always be ON whereas the motor is on and off at times.

[fairdeal]

When the motor (YAM command link) is turned on, the YAM GPS receiver can be selected on the Garmin MFD with the J1939 link to the YAM multihub.

Interesting, although not surprising...

While not absolutely certain,
I do not believe the GPS 19x that is connected to the Yamaha hub
is communicating via J1939, but rather NMEA 2000.

I am certain that the Garmin is able to receive and utilize
NMEA 2000 messages via its J1939 port.

I suspect your Yamaha hub is concurrently 'hosting' both J1939 based data
(engine and control Command Link Plus communication)
and the NMEA 2000 output of the GPS 19x.

I think you have several ways to 'share' one, or both, of the GPS 19x units
between the Yamaha system and the Garmins.

The Gateway should do that, yes.

Another way, would be to connect the Yamaha backbone,
and the NMEA backbone,
so that they form one single system,
(and you could choose either common power,
or separate power to each)

[barcodepesca]

I will try the gateway path. The YAM command link is not connected to the NEMA 2000. Its only link to the outside is the J1939 to one of the 2 MFD's. And note, Garmin are explicitly saying that this is one way - the MFD cannot transmit out from the J1939 port, stated in the 84xx manual. So I hope this gateway is 2 way otherwise I am stuck with 2 GPS receivers and having to relocate 2 instead of 1.

[fairdeal]

I will try the gateway path. The YAM command link is not connected to the NEMA 2000. Its only link to the outside is the J1939 to one of the 2 MFD's. And note, Garmin are explicitly saying that this is one way - the MFD cannot transmit out from the J1939 port, stated in the 84xx manual. .

Let me be clear -
I am suggesting the Gateway to be used in the way Yamaha intends:
to be connected between the Yamaha hub
and the NMEA 2000 network that the Garmins are on -
you'll need to add a Tee -

The Gateway is specifically designed to allow GPS data present on the NMEA 2000 backbone
(the GPS 19x) to pass "inward" to the Yamaha display.

You state that you have observed that the Garmins already 'see"
the GPS 19x on the Yamaha hub
via their J1939 ports.

[barcodepesca]

Yep. Thanks for the conversation and advice Fair Deal. I will get the parts and install and let you know. Will take some time given the general supply and transport issues at present.

[barcodepesca]

Followed up with Yamaha and the dealer... 2 GPS receivers are required, one for theYAM system and one for the Garmin chartplotters. Yam system wants to see the YAM GPS data on the main harness when you have autopilot and the joystick options added. And it cannot get the information from the NEMA2000 gateway.

[Waggs407]

Very interesting.

Would you try an experiment?

- disconnect the NMEA 2000 cable from one of the Garmins
- take the cable that currently goes to the Garmin J1939 port -
(from the Yamaha hub)
and, instead plug it into the Garmin's NMEA 2000 port:

does the Garmin then 'see' the GPS 19x that is on the Yamaha hub?

if it does,
did you say you have both Garmins currently connected via J1939?

what do you get,
if you connect both of those "J1939" cables to just one of the Garmins -
one cable to the J1939, one to the NMEA 2000 port?

does that still give you the "Yamaha page"?
and the Yamaha's GPS 19x?

So this is exactly what I did (before reading this post) when I was trying to tie my CL5 to my Garmin8612. The Garmin recognized the Yamaha info, but the CL5 threw alarms. Codes: 156 & 321 both for loss of communication with DES steering. I put everything back like it was and still the alarms and codes. And the DES is disabled. I reset the CL5, I have left power off for days, still the same alarms and codes.

Any idea how to get the Yamaha network to recognize the DES again?