Originally Posted by Topp dawg
My tach has a 5 wire plug.
7 volt power
12 volt power "for nighttime illumination only"
data "This is the one that tells the gauges what information to display"
The data wire can only be between 3 and 6 volts. I do not think a trickle charge method would work. I attached a picture from the medallion troubleshooting guide.
In that case I would go to my junk drawer of old cell phone chargers until I found one that was between 3 and 6 volts. Cut the leads off, hook to the correct posts and see what happens. Just make sure the output on the power adapter says DC of course.