Tweet
tach not working.checked power and ground and both are fine. has 12 volt and good ground.the green signal wire has 10 volts to it. replaced rectifier and tach but still no such luck.any help greatly appreciated
-
-
No ideas from anyone? Any little bit of info helps -
Hang tight dude...Comment
-
Is the tachometer itself known to be working OK?
If you changed the R/R it would appear that you suspect the motor as being the problem. Correct or not?
Why was the R/R replaced? It does not drive the tachometer.
Do you have a spare 120V AC/12V DC wall wart around? You can use it to drive the tachometer to verify that the tachometer works correctly.Last edited by boscoe99; 07-24-2016, 07:31 PM.Comment
-
Betting prob not?Comment
-
Tach is new from package. Man at boat shop said if the tach didn't work it was most likley the regulator.he also told me that the green wire in the harness shouldn't have current and mine has 10.4 volts with the key on engine not running. Not sure what a wall wart is so I'm guessing I don't have oneComment
-
A wall wart is one of those things that are plugged into a receptacle at your house to supply power to a number of devices. It is technically a transformer. Converts 120 volts AC to 12 volts DC. Over the years lots of folks wind up with a bunch of them for stuff that has broken or is no longer used.Originally posted by bigred4749 View Post
It can be used to power up and test a tachometer.
https://www.google.com/webhp?sourcei...ormer&tbm=shopComment
-
Power inverter I do have lol. Is the green wire that signals tach suppose to have voltage? Boat mechanic told me it wasn't suppose toComment
-
being most tach signals come from the lighting coil on the charging system, I believe it will have AC voltage being it is before the RR.
the tach uses the number of pulses not the voltage.
I guess they look like a wart on the wall when plugged into an outlet. strange name Wall Wart.
makes you wonder who came up with that name for them.
Bosco what reading should he get when hooking one up?Comment
-
Some Yamaha tachometers do get their RPM signal from the lighting coil. The F115 is not one of them. The lighting coil on the F115 provides AC voltage to the rectifier/regulator only. There is no connection between the R/R and the ECU.
The pulser coil on the F115 provides AC voltage to the ECU. The ECU provides AC voltage to the tachometer.
I never thought to check the green wire for the presence of AC volts when the engine is not running. There may be voltage but it won't be AC. Don't see how it could be.
We can presume that the tachometer works. If so, and it is not functioning with the motor then that would mean either a faulty ECU or faulty wiring. Before tracking a wiring or ECU issue I would first want to make damn sure the tachometer functions. There are a number of ways to do that. I just found it easy to use a surplus AC/DC transformer that I had laying around.
Where the hell is fairdeal? We need him to fire up the test department. Measure AC and DC volts on the green tachometer wire with the key on but motor not running. Then start the motor and see what the AC voltage is on the green wire. Better still, if his multi-meter has a frequency setting he can use that to see what is to be seen.Comment
-
How do I go about checking tach with the wall wart. I doubt 2 tachs are bad but gotta start somewhere. The original tach and a brand new tach out of the box both do nothingComment
-
OK. re F225TXRD, Green Tach lead to groundOriginally posted by boscoe99 View Post
Key on, engine off:
DC reading ~290 mV
AC reading 0 V (naturally)
Engine idling, Yamaha tach reading "7" :
DC reading 13.3 V
AC reading unstable, "bouncing" from ~4.4 - 32
Hz reading unstable ranging ~75 -82
here's a video of the running test
https://vid.me/ScR6Comment
-
I would think hooking one lead from the secondary to the tach signal in and one to ground .Originally posted by bigred4749 View Post
power up the tach with 12 volts and then plug in the Wall Wart.
I hope Bosco will correct me if I am wrongComment
Comment