How 2: Wire A Rev Gauge

[ste91]

Until today I myself was a complete beginner to wiring, hadn't touched it before, didn't have the slightest idea what to do or how to do it.

Here is a guide on how to wire a basic rev gauge (tachometer/rev counter/rpm gauge/whatever else you like to call it).

It may be a bit long-winded but I'll try to include every little detail so anyone who is clueless like I was can do it with ease.

What you will need other than the gauge itself:

• wire (get a good length of it)
  
• straight wire connectors (the spade type ones are what I used)
  
• block wire connectors (for splicing into other wires, can't think of a way to describe them)
  
• "U shape" connector for the ground wire
  
• tape (for taping wires together and securing joints)
  
• wire cutters/pliers/scissors (either one will do)
  
• screwdrivers
  
• and maybe a torch
  

You can buy all the wires and the connectors you'll need from Maplin for no more than £10 at the very most.

You might need a torch if you need to go under the dash.

Ok, first you'll want to take out the passenger side panel (the glovebox), there are 4 or 5 screws/bolts then you just pull the whole thing out, be careful there isn't anything heavy in the glovebox as it will fall open when you do this.

Once that is out of the way, you'll want to measure up roughly the lengths of the wires, and where you want to position your gauge.

I put my gauge to the right hand side of the dashboard, next to the A pillar, and have pushed the wires down the tiny gap between the A pillar and the dashboard. This has made it nice and neat and there are no wires showing anywhere.

I have all my wires underneath the dash, for this bit you will need a torch to be able to see properly, and you must route the wires so that they do not interfere with the pedals. I took mine right underneath the dash, past the centre console, into the passenger side which is why I said to take out the panel with the glovebox.

So now onto the wiring. My gauge had 5 wires altogether, it ended up being 3 as some could be joined together.

My gauge has the following wires:

Red - Power source when the ignition is on

2x Black - Ground

Green - RPM signal

Orange - Light for the gauge

Yours may be different, check your instructions if you are unsure.

I joined my two ground wires into one, and the power for the gauge and power for the light into one. That takes it down to 3 wires.

The ground wire is simple, using the "U shape" connector, find a good ground where there's a bolt or screw, (there are a few behind the glovebox panel that you should have removed, easy to find) undo the bolt slightly, put the U shape connector behind it, and do the bolt back up. Job done.

The power wire is next. Take out the clock, and look on the back of it, you should see four wires going into it, and to the side of where the wires are connected in it is written what each of the wires are. Using a "block connector" (can't think of a better way to describe them) splice into the wire which is labelled "Acc (+)". Then put the clock back in. If you do this the same way as I have done it leaves no wires showing and is very easy to get to.

And finally the RPM signal, for this you will need to run the wire through the firewall. There is a hole (there's a rubber bung it in) to roughly where the fuel lines run up the back of the engine bay. Take the wire through here, up to the diagnostics box. Inside the diagnostics box there is a label inside showing what each connector is, you want the one on the end called "Ig-" which is a spade connector so it's really easy to connect to if you bought some spade connectors.

So that's it all wired up, start the car up and try it out. Give the car a little rev just to make sure the needle goes up properly, there might be a switch on the back of your gauge for selection of how many cylinders, make sure your settings are correct.

And there you have it, a fairly quick and easy way of wiring up a rev gauge with no messy wires hanging out anywhere.