Help with Yamaha tachometer wiring

[Scoutpilot]

Hi All, I am hoping someone can help here. I have a new to me 2005 Scout Abaco and (F225 Yamaha production date dec 2005) Only 54 hours on boat and motor. Had it completely serviced and I am loving this rig.

The tach gauge reads full up and blinking. We checked the trim sender and it was reading erratic so ordered a new one here via boats.com, Well installed new on and it still reads full up and the new sender ohm chk is OK. Traced all wiring and connectors for continuity and all is good. I can bypass the wiring and connect directly to the tach and sender reads correctly. Note all wiring checks out OK all the way the the tach. It's weird but I'm thinking it has this adapter that may be incorrectly connected to the tach. The dip switches are all correct and the tach reads fine when directly connected to the pink and black trim wires from the sender directly. Any help or advice it has stumped me and the Yamaha tech that has worked on this. I have attached pics and hoping you pros might help. Thanks much.

[boscoe99]

Attachments won't open for me.

How many four pin nylon connectors are attached to the wiring coming from the back of the tachometer? One or two?

How many four pin nylon connectors are on the trim/oil harness that runs from the tachometer to the motor? One or two?

How many four pin nylon connectors are located in the front of the engine pan that are connected to the trim/oil harness? One or two?

What adapter are you referring to? The correct tachometer will not need an adapter harness between the motor and the tachometer.

[Scoutpilot]

Attachments won't open for me.
Thanks so much for the prompt help boscoe99

How many four pin nylon connectors are attached to the wiring coming from the back of the tachometer? One or two?
- two four pin connectors

How many four pin nylon connectors are on the trim/oil harness that runs from the tachometer to the motor? One or two?
- two four pin connectors

How many four pin nylon connectors are located in the front of the engine pan that are connected to the trim/oil harness? One or two?
- one four pin connector. All pinks with tracers from engine side connected to 2 greens w/tracers and white w/red tracer, blue w/white tracer
- one capped four pin with orange, pink, black, grey

What adapter are you referring to? The correct tachometer will not need an adapter harness between the motor and the tachometer.
At the tach end there are two four pin connectors. one is orange, pink, black, grey - plugged into matching colors and series on tach side.
The other is 2 greens w/tracers and white w/red tracer, blue w/white tracer - then there is a 2 wire adapter that plugs between with green w/white tracer and green w/red tracer - that plugs into the tach side four pin connector matching colors in series.

To me it appears that the capped four pin connector at engine goes to tach and and adaptor seems like it's out of place. Hope that makes sense. if possible I can email you the pics they are super clear and show the connections. Also the tach is stamped 29C on the back if that helps.

[boscoe99]

There are two adapter harnesses. I am guessing that maybe the wrong one has been used. One is a -00-00 and the other is a -10-00. Easy to get them mixed up.

The solid pink wire in the engine harness is used for the trim signal. Hopefully, there is a solid pink wire in the trim/oil harness. But maybe not. Yamaha is bad about not being consistent with their wire colours when crossing a connector. From the trim/oil harness the solid pink wire (if there is one) should connect to the solid pink wire going to the tachometer.

Just check to make sure that whatever colour wire the engine harness pink wire connects to in the trim/oil harness is the same colour that is connected to the solid pink wire on the tachometer.

Here is the configuration that you want:

[boscoe99]

Thanks for the clear information by the way. I once asked a guy about five times for this and he would never give me what was needed. He got mad at me for not knowing how his motor and boat were configured.

[Scoutpilot]

Thank you bosco ( you are like a virtual yamaha guru) This has helped so much. and I agree its like deciphering code to understand the changes in yamahas wiring from the 2004 - 2005 years. At least to me.... I created a photobucket account and hope you can make this out. don't see any type of adapter like the diagram you provided. just that 2 wire adapter to the tach.

[Scoutpilot]

Aha! I am thinking the adapter is connected incorrectly I just re read your reply. so pink wire from engine to green w/red tracer at connector - so maybe the connectors are reversed to the tach and the green wires and adapter connect the the pink, black, grey orange. it would only be feeding the pink wire and i believe grey wire. ??

[boscoe99]

Looks like the wrong adapter harness has been used.

From your photo it appears that the sender pink engine harness wire connects to the white wire with a red tracer in the trim/oil harness.

You can see that the white wire with the red tracer is not connected to whatever jumper harness was used to connect one end of the trim/oil harness to the tachometer. Thus, you have no trim signal to the tachometer.

6Y5-85335-00-00 YAMAHA ADAPTER, -81 TACK FO

http://yamahaoutboards.com/Marine_Ri..._Catalog/#70/z

[Scoutpilot]

Thanks you this all makes sense now. Really appreciatte it

I think I am having a virtual bromance with ya bosco. If ya ever are on the GA coast or in islamarada I'm buying. (Beer or whatever your drinking that is)

OK this makes sense and possible this tach was put in at dealer or factory with older 2 plug unit. without the correct adapter harness. Was looking close at the adapter and think why cant i just connect the red/wht wire that connects at the engine side to the pink trim wire that goes to the tach. I jumped it and tested and it works perfect. so I still leave the two grn and grn/w red tracer connected at the tach (oil pressure and over temp) take that red/wht wire and connect it to the pink wire on the tach side. I did a dry run with it connected this way and all shows good - trim/oil press/over temp. Does that seem ok to you? Save me time and $ ordering and I can get on the water this weekend and make a good connection that will not interfere with a future tach change if needed.

Ahh Yamaha memories. ( I was a motorsports district manager in training back in the late 80's early 90's and my office was across from the yamaha parts and service guys and training center. Good times and a great bunch of folks. Heck an old friend of mine headed up the yamaha factory training and wrote all the early training material....) all I cared about was motorcycles back then.

[boscoe99]

However you can get the correct wires in the engine harness to connect to the corresponding correct wires in the tachometer will work.

Some folks cut and hard wire. I don't recommend it.

The way that the Yamaha connectors and the female/male pins/sockets are arranged there is no good way that I know of to jumper the white wire with red tracer in the trim/oil harness to the pink wire on the tachometer. That is what the Yamaha adapter harness does.

You now know what needs to be done. However you reach the objective is up to you. Go for it.

Since you will be using a bastardized system it is suggested that you verify the low oil pressure and over temperature indications on the tachometer are correct.

I am in Kennesaw, Georgia. About a mile from the Yamaha place. Back in the 80's and 90's I think Yam was on the other side of town. Unless you worked in Cypress, in which case it was across the country. Kennesaw, where the law says every home owner has to own a firearm.

I sometimes go to Savannah. Great spot on Tybee Island for sea food. I will drink a beer and pretend that you paid for it.

[rodbolt17]

the pins will pop out of the connectors and you can rearrange your wires in the connector to make it work. typically I have to add a ground wire for the trim sender.
nice thing about trons, trons don't care what color they are wearing.

[Scoutpilot]

Thanks everyone, Well my trim display is working perfect. I did do minor surgery and clipped 2 wires at the tach side and made a nice new connection for the trim.
I couldn't use the existing pins they were male to male or female to female. Checked the oil press and temp and signal and all is good. I know a some will say you don't need the trim gauge. but I find it helpful and get used to looking at the gauge in relation to the motor noise and it helps when letting someone else drive the boat. I am thinking that maybe the gauges had been replaced at the dealer. This boat has been at a dealer for I think 8 years. I suspect the gauges may have been sun-damaged and replaced with whatever they had in stock. The engine connected to the Yamaha diagnostics shows 50+ hours when i got the boat. The tach shows 2 readings when scrolled in the menus. one 33 hrs and the other 37 hours. I am thinking this is due to the replaced tach.

Anyhoo.. hope this helps some other folks with similar issues and thanks to Bosco and Redbolt you guys make this forum awesome.

[boscoe99]

Thanks everyone, Well my trim display is working perfect. I did do minor surgery and clipped 2 wires at the tach side and made a nice new connection for the trim.
I couldn't use the existing pins they were male to male or female to female. Checked the oil press and temp and signal and all is good. I know a some will say you don't need the trim gauge. but I find it helpful and get used to looking at the gauge in relation to the motor noise and it helps when letting someone else drive the boat. I am thinking that maybe the gauges had been replaced at the dealer. This boat has been at a dealer for I think 8 years. I suspect the gauges may have been sun-damaged and replaced with whatever they had in stock. The engine connected to the Yamaha diagnostics shows 50+ hours when i got the boat. The tach shows 2 readings when scrolled in the menus. one 33 hrs and the other 37 hours. I am thinking this is due to the replaced tach.

Anyhoo.. hope this helps some other folks with similar issues and thanks to Bosco and Redbolt you guys make this forum awesome.

Glad you got it all working correctly.

Pins and sockets don't do queer stuff.