2008 150 txrg starts and shuts off constantly

[rodbolt17]

don't know about non US market stuff.
here in the US market Yamaha had an issue with the early water pressure and speed sensors for command link.
the diaphrams would leak and allow water to be forced up the insulation to various other sensors and the ECU.
this could cause a variaty of stupid issues.
sometimes it will cause the ECU to "see" the wrong baro pressure.

other than water pressure or speed, any sensor that fails is unplugged or out of range will cause base timing to fix at 10*BTDC.
this will cause an idle speed of about 1100.
depending on what failed top speed may or may not be reached.
the ISC is NOT, did I ever mention NOT monitored for faults by the ECU.

[boscoe99]

It is strange that a Command Link water pressure sensor is installed if Command Link instrumentation is not installed.

Quote
ok that helps a little better and no I don't have command link.
End quote

Is engine data being supplied to an MFD? Perhaps the optional water pressure sensor was installed to get water pressure data to a chart plotter.

As noted, early pressure sensors had a high failure rate. Even later pressure sensors are not immune from failing. One failure mode is where water gets from the water side of the sensor to the electrical side. All sorts of strange anomalies can pop up. If you were to call Yamaha USA and report seeing stuff that is just not making any sense at all, they will ask if the motor is Command Link equipped, and if so, are the water pressure sensors installed.

If so, the wire harness connectors need to be inspected for the presence of moisture and/or corrosion. At the pressure sensor connectors (two of them) all the way to the engine ECU connector. If you have not done so, that is an inspection that you might want to do.

The oil pressure sensor is similar to the water pressure sensor but they have different part numbers. Here are some photos showing the differences between the two types of sensors and the earlier versus the later versions.

[TownsendsFJR1300]

Not to hi jack and a quick question.

Without CL, are there any issues (F150 US version, 2006) with those sensors leaking/failing or are the specific to the CL set up?

Very interesting thread, great pic Boscoe, lots of info.. Tks..

[boscoe99]

Not to hi jack and a quick question.

Without CL, are there any issues (F150 US version, 2006) with those sensors leaking/failing or are the specific to the CL set up?

Very interesting thread, great pic Boscoe, lots of info.. Tks..

The water pressure sensors do not come with the motor. They are optional devices to be added based on customer preference. Generally they are added (but not always) when Command Link instruments are installed. With CL instruments and the sensors installed, water pressure and water speed can be displayed on a CL gauge.

A boat/motor could have (1) no CL instruments and no pressure sensors (2) CL instruments and no pressure sensors (3) CL instruments and pressure sensors, (4) no CL instruments but pressure sensors [to display pressure data on a chart plotter for instance) and God only knows how many variations thereof.

If and when the sensors are installed there is then the possibility that they can fail. If a motor does not have the sensors installed then there is no risk in them failing. Only if and when they are installed is there the risk.

Was that too many words to answer your specific question?

[arctic 1]

it is funny as we say all this I don't know much about command link but I am willing to bet it was equipped with it as it came off a fisheries boat from the Canadian government . I bought it at a auction with only 125hrs on it

And on the front of the engine there are a few connectors with no where to go as I always assumed it was because it was duel application.

But I would bet my last dollar that the fisheries boat was either hooked up with a chartplotter or command link

so boscoe the new sensor is the one I would need?

[arctic 1]

or I wonder is it possible to by pass this or is the motor built like this from factory

bare with me here as I am learning something new every day

[TownsendsFJR1300]

The water pressure sensors do not come with the motor. They are optional devices to be added based on customer preference. Generally they are added (but not always) when Command Link instruments are installed. With CL instruments and the sensors installed, water pressure and water speed can be displayed on a CL gauge.

A boat/motor could have (1) no CL instruments and no pressure sensors (2) CL instruments and no pressure sensors (3) CL instruments and pressure sensors, (4) no CL instruments but pressure sensors [to display pressure data on a chart plotter for instance) and God only knows how many variations thereof.

If and when the sensors are installed there is then the possibility that they can fail. If a motor does not have the sensors installed then there is no risk in them failing. Only if and when they are installed is there the risk.

Was that too many words to answer your specific question?

Naw, I follow. Just trying to head off a potential issue, (which I don't have) and now know what to look for (and learned a bunch!). Thank you!

[boscoe99]

it is funny as we say all this I don't know much about command link but I am willing to bet it was equipped with it as it came off a fisheries boat from the Canadian government . I bought it at a auction with only 125hrs on it

And on the front of the engine there are a few connectors with no where to go as I always assumed it was because it was duel application.

But I would bet my last dollar that the fisheries boat was either hooked up with a chartplotter or command link

so boscoe the new sensor is the one I would need?

If you are not using Command Link gauges and/or don't care about having water pressure or water speed displayed any where then simply don't have the optional sensor(s) installed. One less thing (or two) to fail.

There is a bright white connector in the front of the engine pan. That is the connector for the Command Link data output. If not used it will be capped off. There are one or two other ivory nylon connectors that may or may not be in use. They are for the trim information and the warning signal information if and when Yamaha gauges are used. Finally, there may be two single wire/pin connectors with pink wires going to them. These two connectors get attached to each other if and when a CL tachometer is used. They are disconnected if a conventional trim gauge is used.

[arctic 1]

ok boscoe sounds about right

I will see what I am working with when I have a chance to look at it

right now all I am using is a reg Yamaha digital rpm gauge I was never able to hook up my trim meter and I guess that's why I can't find anywhere to plug in the harness from the gauge

So sounds like I can bypass it as I have no use for it and spending 300 bucks on a new sensor

[arctic 1]

Found all the wires for the trim
So can I simply unplug the water sensor When I do it seems she runs bad

[boscoe99]

The engine should run the same with or without the sensors being installed. Did you inspect the sensor connector for the presence of moisture and/or corrosion?

Let's make sure we are talking about the same sensor connector. See the diagram below

[arctic 1]

def the same sensor

one of the pins on the connector was dirty and had sighns of water in it .

I cleaned with contact cleaner but I guess I should inspect a little more

[boscoe99]

def the same sensor

one of the pins on the connector was dirty and had sighns of water in it .

I cleaned with contact cleaner but I guess I should inspect a little more

You need to pull the connector to the ECU. Inspect all of those pins and sockets as well.

As hard as it may be to believe, water can migrate across a pressure sensor, into the wire harness, and make its ugly way all the way to the ECU connector and possibly over into the ECU. On the surface it does not seem possible. You probably don't believe what I am writing because it sounds so illogical. But, it happens.

[arctic 1]

ok will do boscoe

so just unplugging it should do the trick ,I don't need to jump the connector?

And I also done everything you said with the trim wire and the others for the cl are fine the way they atr?i also have a pretty big gauge red wire there also with a single pin black connector?????

[boscoe99]

ok will do boscoe

so just unplugging it should do the trick ,I don't need to jump the connector?

And I also done everything you said with the trim wire and the others for the cl are fine the way they atr?i also have a pretty big gauge red wire there also with a single pin black connector?????

That is for the alternate isolated charge lead in the event you have a second battery in the boat.