Tachometer - what are the necessary connections

[CBradio]

The copper in the ribbon on the left side of my cluster (temp guage side) recently pretty much disintegrated {I suspect some moisture got in when the car was sitting due to a fault heater valve}.

I went to hook up the tach as a stand alone item- but got a dead response.

My understanding is that the connections are as follows:
Brown wire: ground
Black wire: ground pulse signal
Green wire: positive connection

However, when I plug my tach in, it is not moving.

I am getting a signal to the wires.... the green/white does pass through the temp guage side of things but I {perhaps mistakenly} don't think it should make a difference with the tach.

Is the tachometer not supposed to work on its own? Assuming I am getting correct signals to green, black, and brown wires, Is my tachometer just suddenly broken? Is there something that goes bad in these items?

Any input appreciated

[CBradio]

Another question: how often do these these tachs just konk-out?
Its possible i hookes the wires up wrong once, would i have fried it?

I did a search but didnt find much

[Peter Florance]

Tach will work by itself.
It will work either from coil negative or just 12v pulse signal (I'm running LS2 coils on my e12 and had to generate my own tach signal(

[CBradio]

Thank you Peter.

I am getting good voltage to brown and green wires,
with a pulse from the black wire.

So I am assuming I killed my tach somehow.

Will update when I get another.

[Peter Florance]

Thank you Peter.

I am getting good voltage to brown and green wires,
with a pulse from the black wire.

So I am assuming I killed my tach somehow.

Will update when I get another.

Be sure you have it connected correctly

1 - black
+ green

The other terminal (can't remember label) is brown

[CBradio]

Well I got another tach from a kind member of this board,..

It turns out I burnt the tach out.

The symbols were: +, l, -

The 'l' is for the signal from the coil...

I must have switched them around or something the first time.

Thanks for all the help \(^_^)/

[philipj]

I only see positive and negative markings on the tachometer, just want to be sure that the black wire goes to the negative post (left) facing the instrument or (right) if you were looking at the back.. Thank you.