1) looking for a harness wire energized when the key is in the on position.

2) the negative side of the ignition coil (TACH, TACH TEST, DEC, OR ECU terminal)

 

There are lots of wires in a car. I assume you are trying to hook up an aftermarket tach and plan to tap some wires at the cluster.

Gauge power (on when ignition is on) yellow or black-yellow wires, cluster plug pin C3 or D3.
Ignition pulses (tach signal): blue wire, plug pin D5.

 

Thanks im putting one in my friends 94 civic

 

Look at the fuse block under the dash. Use the #3 or #4 spot.

 

ah ok cool thanks

 

I hooked up the tach to my friends car and all works however the the shift light stays on. any ideas?