Remote display and alarm problem from Yamaha 60HP

[Copinsay]

Hello All

I'd welcome any suggestions to help with the following.

The gauge pictured currently works intermittently. Not simply on or off, but varying in intensity. Sometimes the LCD display (trim, rpm and oil) is very contrasty, other times very faint... And it fades in and out between the extremes.

No particular pattern to this - can be in or out of the water, before, during or after a run.

I'd initially thought low battery voltage, but multimeter and voltage display on chartplotter all show a decent 12.0 volts when idle / not running, and 14.6v when running and under load (ie charging).

In truth, I'm not that bothered about the rpm, trim and oil displays.

BUT what I do want to work is the engine over temp buzzer... I say that after it thankfully went off in the Pentland Firth the other week when a Tesco bag had fouled the water intake on the leg - not something you want to miss.

I mention the latter as when the display is of low contrast or off, the buzzer does not sound when you try to start with the engine up, and so I guess the over temp is not working either....?

As all these functions seem to go off at the same time, so my gut feeling was for a bad earth... But the fading in and out of the display, makes me wonder if it's something else, like some dodgy regulator etc???

Any suggestions welcomed.

Best wishes and thanks

Steve

[jyasaki]

As I recall, the only hard power input is for the lights (usually wired to your nav lights switch.)

The rest of the signals and power come from the motor; I'd guess your problem is a flaky connection somewhere in the wiring harness from the motor to the gauge.

jky

[Copinsay]

Thanks for that - I've redone all the conenctors at teh console, but will do as you suggest at the other end.

The only thing that put me off that path was how the change was gradual, eg fade up and down, rather than jerky like a physically bad conenction tends to be.

Certainly would prefer it to be wiring rather than the CDi unit given the cost!

Many thanks

Steve

[A1an]

I had a very similar problem, the gauge used to come back to life when I used the PT&T, turned out to be a dodgy connection in the multiplug.

[Erin]

Certainly sounds like a high resistance connection somewhere. These can give the intermittent faults and fading that you are experiencing as slight temperature changes and current draw can affect the resistance.

[Copinsay]

Hello All

Many thanks for this - really helpful in saving me some time.

Will have a go and let you know how I get on.

Best wishes

Steve

[ssobol]

An LCD display will fade out as the voltage is reduced (the voltage available to polarize the display drops). This may be external (power problem to the instrument) or internal (power not getting to the display components). Since the buzzer also fails when the display is faint, it would appear to be a problem with getting power to the instrument.

[Copinsay]

Hello All

Have now got the wiring diagram so that will make things a lot easier... here goes!

Steve

[Copinsay]

Hello All

A power cut this afternoon freed me from office work and so I set to tracing the fault in the daylight.

Really useful anyway to have a good poke about the engine, take covers off etc and mechanically test (and WD40 spray) all the bullet connectors for when you may need to look at sea.

AND I seem to have fixed the fault. I lifted the oil level sensor up to check it was working correctly, and noticed that waggling those sensor wires created the fault. So disconnected it, checked it all out, found nothing conclusive but now it's fine.

It did look like it was quite tight where it went behind the oil reservoir and the "Electrothermal valve" (can someone explain what that does - I was assuming the "Fuel enrichment valve" was the electronic choke, but maybe not?) so I've rerouted the cable, and now no amount of wiggling will recreate the fault.

So fingers crossed - at least it's not a mission critical issue.

Many thanks for all your help - I hope this helps others too.

Best wishes

Steve