2017 G2 System Check Tach not working

[depdog60]

Guys,

My tach did not work at all last season and this coincides with a Garmin graph installation that I did at the beginning of the season. I cut the existing hole in the dash larger with a jig saw so there's the possibility I killed it with the vibrations from the saw. But, at the same time I connected it to the N2K network to bring in the engine data. The network was installed with the boat so I added a tee and terminator with aa extension cable to the Garmin. I can see all the motor data including the RPM's on my graph but nothing on the analog tach. I think that I disconnected the tach from the network on the water last year but don't know if I pulled the tee off and reinserted the terminator or not. Before I go buying another tach thinking I killed it during the graph installation, I want to be sure that the tach would work with the N2K connection as well.

[tdt91]

Are you sure your tach runs off of the N2K. I doubt it is. Check for loose wire or disconnected wires.

[joebone1]

what side mount control do you have - if you have the basic side mount there is a seperate harness for your gauges. I don't believe the system check tach works off of the nema.

[depdog60]

what side mount control do you have - if you have the basic side mount there is a seperate harness for your gauges. I don't believe the system check tach works off of the nema.

The premium I think. Yea, that makes sense that it doesn't work off the network now that you guys mentioned it.
At least I can order the replacement with more confidence now, lol.
Thanks for the help.

20180316_111147 (4).jpg

[depdog60]

I found out today that the tach does work without the Garmin turned on. Turn the graph back on and no tach.
The graph is powered separately from a dedicated wire and the I connected the graph by adding a tee and terminator to the backbone that was already under the dash.
Looking at the picture, the N2K is connected to a D/A converter for the gauges. I connected the graph direct to the Tee that bypasses the D/A and then can only see either signal but not both? Does that makes sense?

Premium Control & Sytemcheck Gauges Schematic.jpg

[blkfalc4]

You added a tee AND a terminator? Should have only 2 term resistors on each end of the nmea trunk.

[depdog60]

You added a tee AND a terminator? Should have only 2 term resistors on each end of the NMEA trunk.

Thanks Mike. After reading your post I took the graph out b/c I couldn't remember what exactly I did. Apparently I took the tees apart and put the new graph connection (gray tee) in the middle. Not sure why I did this but I did change it by putting the graph connection at the end of the branch, second picture. BTW, the Tee with the gray cable is the one that goes to the D/A converter.
Graph Tee B4.jpg

Graph Tee After.jpg