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Yamaha Command Link Tachometer for F70
|Author||Topic: Yamaha Command Link Tachometer for F70|
posted 12-15-2013 11:37 PM ET (US)
I installed a Command Link Tachometer to my F70 Yamaha. All I can get for readings from the tachometer are RPM, Battery Voltage, and Engine hours. I installed the remote water pressure sensor and no other devices. The only thing I did not install was the blank caps provided to the bus bar or main terminal. Which I just remembered. Could [failure to install blank caps] be the problem? Ignition works fine, binnacle operates correctly. Seems I missed something basic. Thanks
posted 12-16-2013 06:51 AM ET (US)
I presume that the "blank caps" are terminators on an NMEA 2000 network (the "bus bar") . The terminators are required. It will not work without them.
posted 12-16-2013 10:28 AM ET (US)
Weird. I installed all the caps. Checked all the connections, and everything seems to be hooked up correctly. I guess it isn't. I'll call the Yamaha dealer when it opens. Thanks of the help.
posted 12-16-2013 10:47 AM ET (US)
Blank caps are probably just that, caps that cover unused ports. Terminators are something different. Without the network terminators there could be a malfunction of the network.
posted 12-16-2013 10:51 AM ET (US)
The data that can be read on a network display is dependent on the data being sent by the outboard engine. You should verify what data can be sent from the Yamaha F70 to the network. It is typical that on outboard engines of lower horsepower there is a limited amount of data available from the engine.
posted 12-16-2013 11:08 AM ET (US)
From what I understand it [i.e. a Yamaha F70] should be able to send trim angle, water pressure, water temperature, oil pressure--things like that. I have something either not connected or hooked up improperly. Will advise. Thanks.
posted 12-16-2013 12:39 PM ET (US)
If you are getting one NMEA-2000 datagram from the engine on your Yamaha Command Link Gauge, you should get all of them. That is to say, the network must be working well enough to send one datagram so it should be working well enough to send any datagram. If your engine can send other data, such as engine tilt or trim, it would be sending that already to the network. If the display device can display that data, it would be displaying it. I don't believe there is any way to configure a network so that the network knows it should only allow a certain datagram to pass. If the network passes one datagram, it should pass all datagrams. On that basis, the network is not a source of your problem in being unable to display the engine data you are seeking from the engine.
posted 12-16-2013 02:31 PM ET (US)
I went to the local Yamaha dealer who had an F70 in the showroom. There are two cylindrical connectors under the cowling at the front of the motor he showed me. They are taped together at the factory with 'Yellow' electrical tape. Apparently these are used for 'Analog' gauges in their current configuration. To use a 'Digital' or 'Command Link' gauge, you must un-tape the two conectors, remove their caps, and plug them in to one another. Apparently this tells the engine to start sending digital signals to the gauge.
The battery [voltage], RPM, and engine hour readings I was receiving apparently aren't part of the same digital-over-analog' signal highway. Anyways, glad I got it solved. Until the next thing. ;-)
posted 12-16-2013 03:38 PM ET (US)
The engine does not send data "to the gauge." The engine sends the data to the network. The gauge is on the network. The gauge gets the data from the network.
I don't think those cables really control the initiation of the engine sending data. It is more likely that on those cables there are two circuits. One circuit is a source of analogue signals, that is voltages or resistances, which are normally connected to analogue gauges in an analogue gauge system. The other circuit is a destination to analogue sensors that are part of the digital instrumentation system. When you connected the two circuits you were probably providing the digital instrumentation system with analogue signals for some of the digital systems sensor inputs. This would be typical for engine trim. Engine trim comes from a resistive sender. Normally this sender is connected to a trim gauge in an analogue system. If you want to get trim data on a digital system, you have to connect the trim sender to the digital system. That is probably what happens when you connect those cables.
Usually the Yamaha owner's manual gives good advice on setting up their gauges. I browsed the owner's manual for the Command Link Multi-function meter (square) at
I did not see any advice on making those cable connections under the cowling. Nor was there any in the owner's manual for the F70 at
Perhaps Yamaha considers the rigging of the Command Link Multi-functioni neter to be something a dealer ought to undertake.
posted 12-16-2013 10:52 PM ET (US)
Cool, thanks for the intel. I'm glad I installed everything myself. It was all very straight forward. Basically plug and play. I don't feel bad for not knowing that those 2 connectors needed to be un-taped, un-capped, and connected, since I'm not a motor technician. But,like I said, it's all very basic. All the other connections were where they should be. By installing it myself i now have a much better understanding of the system (even though it sounds like I know less than zero). Thanks again, and maybe this will help someone else in the future.
posted 12-24-2013 10:01 AM ET (US)
Keeper, I went with an all-Yamaha command link bus rather than NMEA-2000, but same basic setup as you. I don't recall which of the manuals explained that setup step (I have the F70 factory service manual and the Command Link rigging guide) but it was pretty clearly covered.
The reason for my post was to correct your reference to oil pressure - the F70 does not have an oil pressure sensor, so while the gauge can display it, the motor doesn't send it. If I ever get around to it (I probably won't) I may see if an oil pressure sensor from a larger Yamaha can be installed in place of the simple pressure switch.
posted 04-01-2014 10:22 AM ET (US)
I just purchased the same motor [Yamaha F70], but a dealer hasn't yet installed it.
Keeper---Did you ever conclusively determine that the F70 outputs oil pressure and water temperature data datagrams?
If so, can that digital data be output to analog gauges via some type of modem, or strictly the Command Link Tach?
My install won't be started for at least another 2 weeks, so I would like to know if Command Link Tach. is worth the extra costs of related items such as the bus and harnesses? The Tach itself is relatively reasonable cost, the added cost of requisite preipherals and time to install changes things quite a bit.
I could go path of least resistance and use the 'Pro-Series' Digital tach, but that leaves me with analog water, oil--if even possible--which, without some type of modem, requires interuupting at least an oil line--which I won't do to this engine.
Anyone else, correct me if I've mis-interpreted.
posted 04-01-2014 10:30 AM ET (US)
I just read more closely the reply by 'Tedious'; that simplifies it somewhat. I'll go to the Command Link Tach. manuals as well.
I guess Yamaha concluded on these smaller engines that water temp isn't as critical as oil pressure.
posted 04-01-2014 10:31 AM ET (US)
I do not think you need a modem. A modem is a device that modulates and demodulates a signal onto another signal, called a carrier signal, usually for the purpose of electrically transmitting the signal a much longer distance than could be accomplished with the baseband signal itself. In a small boat, the electrical signals only have to travel a few feet, and they are seldom, if ever, modulated onto a carrier signal for that transmission. They are all sent at baseband, or DC signaling.
posted 04-01-2014 09:11 PM ET (US)
I have just had a Yamaha F70 installed on my Montauk. I went with the "standard" digital tachometer rather than the command link. I also purchased the Yamaha adapter cable for NMEA 2000 along with a Lowrance network starter kit, LMF 200 gauge and a EP-85r.
The Yamaha puts out Engine Hours, RPM, fuel consumption, alternator voltage, and water temperature by default.
It also reports engine alarms, I simulated one by disconnecting the temperature sensor on the engine which immediately showed a check engine alarm on the LMF 200. Interestingly the Yamaha digital tach showed no alarm at all!
If you connect the yellow capped wires near the NMEA connection under the cowl it will also report trim level over the network. However it seems that if both the standard digital gauge with trim meter and the yellow connectors are connected at the same time it skews the trim reading somewhat. So it should probably be a either or setup.
If you purchase the water pressure sensor kit you can also get water coolant pressure reporting on the network. I plan to do this soon to replace my analog pressure gauge with another LMF 200.
I am actually so pleased with the Lowrance gauges I may replace my Yamaha tach with an LMF 400 as well. This would make a cleaner look, including synchronized backlighting, more flexibility, and the data presented is more detailed. For instance engine hours is reported in tenths and RPM are to the single digit. I also found you can have a page on the Lowrance flash when a value changes such as engine trim so I don't have to dedicate a whole gauge to it.
My understanding is Command Link is NMEA 2000 with non-standard connectors and topology. The NMEA 2000 connector is the Command link connector. There is also the standard digital tach connector and diagnostic port under the cowl.
I actually purchased the Yamaha YDS diagnostic software and usb adapter software for the engine as well. The diagnostic port on the Yamaha engine is an OBD II port with a non-standard connector. The kit I purchased adapts the connector to a standard one the same as you would find on your car. The usb adapter is a inexpensive usb to OBD adapter that shows up as a serial port in Windows. The Yamaha YDS software reads much more information from the engine including fuel pressure, injector timing and air pressure. It also displays RPM breakdown by engine hours and can read and clear diagnostic codes such as the temp sensor one that I triggered purposely.
posted 04-02-2014 03:05 PM ET (US)
jharrell, if I understand your last post, you have the Yam digital tach AND the LMF200 installed concurrently?
Does Yam require at least one of their gauges be included at instal to comply with warranty requirements? I guess I could ask dealer.
The LMF200 sounds like a better device for the money than the Yam products.
My objective is to have rpm, hour meter, alt volts, trim position, AND either water temp or oil press in the least expensive way.
The dealer quoted $800 for the CL tach, Main Bus, two Bus Harness, electronic cooling sender and install.
posted 04-02-2014 06:44 PM ET (US)
Yes both concurrently, they use separate connectors, here is a pic:
Here is a pic under the cowl, the connector with 4 pink wires is the standard digital tach, the one with white and blue wires is the Commandlink/NMEA-2000 connector:
Here is a pic of the water pressure gauge connection, the white tube goes to my analog gauge, the black connector with grey plug labeled "W" would be where an electronic sensor would connect instead:
The basic Yamaha digital tach will show hours,RPM, and trim. The Commandlink tachs will also show engine temp and alternator volts but only as simple bar gauges without much detail I believe. The Lowrance show the same information but in a somewhat more flexible way with more detail, and can do a virtual fuel gauge using the EP-85R. The Yamaha gauges will always show trim as a graphic bar on the right, the Lowrance must switch to a trim page. I believe the command link gauges especially the large square one will show more descriptive engine alarms, the standard tach I have only has small on/off indicators for water or oil alarm.
As far as the warranty without a Yamaha tach, I will have to double check but I do not believe it's an issue. I have an alarm horn that is part of the key-switch independent of the tach and after all the F70 can be used with a tiller and no tach of any kind. At this point I am more confident in the Lowrance alarms because I have seen them work with my engine while the Yamaha tach did not even register a problem. Perhaps if the engine was running it may have.
My understanding is the F70 does not have a oil pressure sender, so it does not report that at all, it does have some sort of on/off oil pressure/level alarm sensor that should broadcast, but it will not report a psi value.
If I was to do it again I might for go the digital tach all together getting the cheapest install possible switching to the NMEA-2000 gauges after as I am now. I just wasn't sure of the capability and usability of a NMEA-2000 Lowrance setup with the Yamaha engines.
posted 04-02-2014 10:47 PM ET (US)
Jharrell- the basic analog gauge is looking better now.
I'd prefer to wait a while and swap it later for the LMF400. Since they're both 3-3/8" hole, I would replace the Yam analog with the LMF. My replacement console is a bit smaller than OEM Montauk and fear crowding it to resemble a Gulfstream cockpit.
My tunnel is going to be crowded.
posted 04-03-2014 07:55 AM ET (US)
The TRIM circuit on most outboard engines involves a resistive sender and some sort of voltage divider circuit. The current for the resistive sender usually comes from the instrument that is going to show the TRIM position. If you connect both a conventional trim gauge circuit and the digital trim gauge circuit to the same sender, there is probably a change in the voltage or resistance or some combination of the two in the new circuit that results, and that affects the reading.
posted 04-07-2014 01:33 PM ET (US)
I thought I would note that over the weekend the engine reported an over-rev alert to the N2K network which the LMF-200 displayed. Nothing was reported on the standard Yamaha digital tach at the time. I received this alert while speed testing my new motor after hitting the 10 hour break-in period. I was trimming and raising my jack-plate attempting maximum speed (which I hit 39 mph for a brief time, 38 mph consistent). While doing this if the engine was trimmed too far or jackplate raised too much the RPM's would go up to 6400 on the tach and the alert would show on the Lowrance gauge.
This is interesting to me as there is very little information on what indicators are supported by Yamaha engines from PGN 127489. So far I confirmed Check Engine and Rev Limit Exceeded on the F70.
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