K11 Pre-Facelift Rev-Counter Wiring Procedures
Ok boys and girls, the first thing you need to do (assuming the clocks are already fitted) is to remove the lower potion of the dash/centre console to gain access to the ecu (the section below the heater dials).
Behind the side panel next to the clutch pedal (Right-hand drive models), there is a very large white plastic plug/connector, screwed into the floor. This is where the wiring harness plugs into the ecu.
Take a good look at the diagram, noting the colour order of the wires.
On the diagram I have arrowed a
Blue & Black wire... this wire runs up to the rev-counter (if you are unsure you can always follow the wire from the clocks, down to the big white connector).
Now at this point I need to assign names to things so that it's easier 1. For me to explain
2. easier for people to understand what I’m saying. When I say "Big White Connector" I am referring to both parts together in the connected state.
Remember that the big white connector is actually TWO connectors, one male and the other female, which are plugged into one another, (there is no need to separate them).
Ok; "side 1" is the side shown in the diagram, with the Blue & Black (rev-counter) wire going into it.
Now if you look at the other side of the connector, ("side 2") in the pin hole opposite the Blue & Black wire, (the pin on side 2, that the pin from side 1 with the Blue & Black wire plugs into) you will notice that there is no wire there. There is no wire going from that pin to the plug on the side of the ecu.
So basically it's an open/incomplete circuit, and what we need to do is bridge the gap.
What you need to do now that we have established what everything is, is this;
1) Cut a section of suitable wire to a size adequate enough to bridge the gap (but not too tight).
2) Plug one end of the new wire into the empty pin I talked about, opposite the Blue & Black wire.
3) The other end of the new wire needs to connect into the signal sending pin in the connector on the side of the ecu. This connector is not shown on the diagram so I can give you no detailed reference other than memory. The signal sending pin is an empty pin that sits between a Solid Black wire and a Solid
Orange wire. Plug the end of the new wire into this empty pin hole and make sure that it is contacting the pin (check that the other side of the new wire is also contacting its pin)
4) Start the engine, if the rev counter does not work immediately then check that the wires have a good contact with the pins at both ends.
5) Now that the rev-counter is tested and working, you need to make secure connections at both ends of the new wire, this is because the empty pin holes don't actually have pins in them since there are no wires connecting them, why waste connectors after all?
There are two ways of doing this, the right way, and the erm... improvised way. :wasntme:
"The Right Way" (Y)
Obtain an electrical kit with crimps and the same sized pin connectors used by Nissan in the big white connector, and then crimp the appropriate pin type (male or female) at both ends of the new wire.
Finally re-connect the new wire to the right pin holes that we have established, and you're done... after putting the dashboard panels back that is.
"The Improvised Way" 
Twizle the exposed copper wire ends of the new wire, stuff them into the correct pin holes and stuff some bluetack, silicon, chewing gum, (anything non conductive) into the hole with the wire to hold it in place. I'm not proud of it but... I used the improvised way, 2 and a half years ago, and it's still working fine to this day. But then I’m a crazy kinda guy and only crazy people should attempt to use improvised mechanics.
Have fun kids,
Professor Porkpie. *geek*