Next logical step???

[Duke86max]

Well I got the new relay in today and plugged it in cranked the bike up and still have no tach. and no power to the fuel pump when the bike is running.

When I first turn the key on the fuel pump will run for the designated 5 seconds and shut off but once the bike is running I have no power to the fuel pump from the relay. I have 12v to the brown and gray wire on the tach. and 12v to the relay from the tach.

What now???????????????????????????????
Duke
1986 Vmax

 

[satariel666]

Gauges, fuel pump relay and the v-boost controler takes a tacho signal from rear right cylinder coil.
If the coil is not triggered from TCI the whole things above may not be working porperly.
Bad TCI-coil?

 

[maleko89]

I would check your signal wire as Przemek mentions. The signal wire does route to the fuel pump as a safety measure so the pump only operates continuously while the bike is running. Signal wire also goes to the tach and vboost. I believe it's gray in color.

 

[satariel666]

I would check your signal wire as Przemek mentions. The signal wire does route to the fuel pump as a safety measure so the pump only operates continuously while the bike is running. Signal wire also goes to the tach and vboost. I believe it's gray in color.

Gray for some early models, mine is using yellow/something.
I wonder how manny colors were used trough all the years :ummm:

 

[maleko89]

I checked my Clymer and it says gray from '85 - '92, yellow AND gray for '93 - '03.

 

[satariel666]

Cool thanks.
Another good info for my notes :biglaugh:

 

[Duke86max]

I have the COP conversion and this was happening prior to the swap so should not be a coil. I have 2 gray wires that go into one terminal on the relay plug and it has 12v there. I also have 12v at both the brown wire and gray wire on the back of the tach. The temp. gauge works and the lights work.

The only thing not working is the tach. and fuel pump. This was happening randomly before I would be riding along and the tach. would go haywire then drop and the bike would cut off but then start back up and it might not happen again for a day or two. Now whatever was going bad has died for good.
Duke

 

[MaxMidnight]

That sounds like a bad/ broken/ burnt. corroded connection or wire.

Assume you have checked continuity through the relevant cables?

 

[tugla]

bad ground wire, maybe just make a few new grounds , frame to frame pieces or one direct to batt and see if that helps.

 

[Duke86max]

Had the tach on the bench yesterday and checked continuity from the plug end to the screw terminal on the back of the tach.

All of the grounds were cleaned and I used star washers to reattach them when I put on the new wiring harness.

 

[Duke86max]

Well it was the TCI got one from Sean and hooked it up, the bike ran for about 10 seconds and the tach. kicked in and so did the fuel pump.

Now to figure out the wiring for the lights.
Later
Duke