Command Link gateway to display Yamaha engine data on MFD stopped working

[Yamaha18]

here is the setup picture - note the yellow trim bar in the MFD

image0 (2).jpeg

[Yamaha18]

I am connecting it to Raymarine Axiom 9" MFD multi-function display instead of Yamaha digital meters. Yes,F70 engine is mechanically control instead of DEC/drive by wire. That is why I need 6YG-8A2D0 gateway to relay F70 digital engine data to my Raymarine MFD. It was working until this weekend. The other thing was it would stop displaying when I put Remote Control into gear. There may be loose connection somewhere in the wiring because the trim display showed solid blue color when I was moving the wires to see which wire was loose. Too bad, the blue trim color in the trim bar didn't stay long enough and it didn't turn into yellow and stay yellow. I know SOLID yellow in trim bar means engine data is displayed.

[fairdeal]

Yamaha 'Command Link' is essentially NMEA 2000
so four conductors:
red=12V+,
black=ground,
and the blue and the white are the data wires.

The wiring for NMEA 2000/Command Link,
when properly configured,
is arranged in a "backbone" - with,
at each end, the white and the blue wires connected via a 120 ohm resistor
like so:




as far as testing 'data wires'
with all the devices 'off',
you should have:
- continuity between all whites,
- continuity between all blues,
- a 60 ohm resistance between white and blue, anywhere


By the way -
I didn't see what Yamaha model you are working with;
but, although Yamaha 'assumes' you will use their Gateway -
if the engine is 'mechanical control' -
NOT "DEC" / 'drive by wire' -
then you really don't need the Yamaha Gateway -
just connect up without it.

[Yamaha18]

I don't know what effect it would have on the Gateway -
but certainly,
measuring 11.2 volts there - or anywhere - is "pathological"

what is the voltage at the battery terminals?
12 and change, yes?
you should have within a couple of tenths of that,
on the red power cable -
and the same on the hot terminals of the multi-hub

Yes, my 12 volts battery is dying and measured only 11.2 volts so silly me. I connect it to a 12.75 volts battery and I am getting 12.50 volts so good for this part. Moving on to check the power inside of the different cables:
(1) cable to Yamaha 70 hp engine bay - I heard humming sound when turning my key so this cable should be good.
(2) cable to Yamaha gateway 6YG-8A2D0-00-00 - To be checked.

How do I check data wires in these cables?
How do I check NEMA 2000 cables and T-connectors?

[Yamaha18]

here is a picture to make sure 12 volts power inside of the CL multi-hub - see picture below.


image0 (1).jpeg

[fairdeal]

I don't know what effect it would have on the Gateway -
but certainly,
measuring 11.2 volts there - or anywhere - is "pathological"

what is the voltage at the battery terminals?
12 and change, yes?
you should have within a couple of tenths of that,
on the red power cable -
and the same on the hot terminals of the multi-hub

[Yamaha18]

Command Link gateway to display 2019 Yamaha engine data on Raymarine Axiom MFD stopped working - troubleshooting help

1. check all fuses - all worked - 1 on RED power cable to CL hub from remote control.
2. I removed the back cover of CL multi-hub and found 11.2 volts on the 2 long stainless steel plates inside the CL multi-hub (Unsure if 11.2 is enough to power all the plugs on CM multi-hub