T25TLRD Tach installation wierdness

[johnboatcat]

I have a 2005 T25TLRD made in 8/04.

So I ordered the tach for the 2005 and newer motor, as a T25TLRD is listed as a 2005 model, which has one plug. When I opened the control center I found that the old tach has two plugs and a two plug wiring harness.



Following this wire to the engine ends up with the two plugs not plugged into anything.


This is the only connector on the engine (besides the two from the tach) that is not plugged into anything. What is it used for?

The old tach works. So questions.

Do I just hook up the other non-plug connector wires on the new tach and forget about the plugged wires?
Do I need some kind of adapter cable?
What is the other non-connected connector on the engine used for?
Did this engine have push to choke and a tilt/trim sender?
Thanks!

[rodbolt17]

your either going to order the adapter to adapt the older tach wiring to the newer tach or buy the older tach.
it was rigged with the older pre 04 trim and oil harness.

[johnboatcat]

I bought the kit so I have the correct wiring harness, but where would it connect on the engine? Thanks!

[rodbolt17]

but you dont.
like I said its wired with the older trim and oil harness.
to make the single square connector tach work your going to have to buy adapter 6y5-85335-10-00 or buy the -82 tach.
your new tach is a -90.
look for tech bulliten 2006-006.
I actually sometimes know what I am doing.
I made yamaha master tech in march of 06.

[johnboatcat]

Does this engine have a six or twelve pole generator type?

[rodbolt17]

hold on, let me look.
but there may be a better adapter.
do you have the tach part number that you bought?

[johnboatcat]

Oh so you are saying that my engine came with a setup for the old type of tach and harness and not the 2005 and greater like it should have?

[rodbolt17]

looks that way.
it came from the factory with a trim sender if it has factory power trim.

[johnboatcat]

I bought 6YR-W0035-E3-00 TACH RIG kIT.

The odd thing is that neither of the plug connectors on the engine end are connected to anything and the old tach is working now. It is just fogging up and is hard to read.

[rodbolt17]

pink is trim send, yours is a two wire sender, gray is overheat visual,black is ground, orange is a 5V reference.
the two pin connector at the motor, green is oil ok visual and green red is oil alarm visual.
there are two possible engine to tach harness's.
the 6y5, what your kit came with has a single white square 4 wire connector at each end.
the older 68f style had a two wire and a 4 wire connector at each end.
to use the older 68f harness on the newer single connector tach will require the adapter.
can you get a pic of the engine side connectors?
not the harness side.

[johnboatcat]

There are no "engine side" connectors. The only free connector on the engine is the one in the photo above which is right next to the main starter fuse assembly. The two connectors that are attached to the harness that runs to the tach are currently not connected to anything and are just lying in the pan after entering the engine. There are no other free connectors. That is why I was wondering where and how either the old or new tach would connect to the engine. Weird.

[rodbolt17]

on the 4 wire engine connector, not the harness between engine and tach, post the wire colors.
its a 12 pole system.
if it only has one engine connector then the adapter was left out if using the 68f harness.

[mudjon09]

tach on t25

i have a 2004 T25,bought a aftermarket tach fron dealer and stuck in the dash , a easy install, works great.
only had to go to the next set of magnets on back.

mudjon09

[rodbolt17]

your original tach is probably older than 04 as it does not have the hour meter built in.
most likly never had the late style 6y5 oil and trim harness.
not required for just tacometer function.
is required for visual indicates and trim indicate.

[johnboatcat]

As seen below the 2004 and 2005 wire harness assy are almost but not identical. Is there a tech manual or something that shows what each of the connectors is used for? I called my local parts guy today and he said he didn't think the T25TLRD supported the other functions like trim/oil/heat. Is there a way to confirm that? Thanks!