Okay - to the wiring.
There are only 4 wires.
Pin 1 - Blue / Yellow to the oil pressure sender.
You can fit Calibra, Astra GTE, Cavalier Mk2 SRi or Frontera combined oil pressure sender and switch units.
Note however that there were many faulty Frontera senders knocking about.
I think I had a couple giving low oil pressure readings.
If you have not got a sensor connected to the gauge (open circuit), the needle will flick over to full deflection, with potential to damage the gauge mechanism.
If this is the case, short the blue/yellow wire to earth / ground, as this will hold the gauge at zero bar. (The needle will not move, and thus damage is avoided)
Pin 2 - Black to an Ignition live supply.
Many people cheat, and wire to the cigarette lighter wiring.
Suitability of this depends on what you plug into your lighter socket.
USB chargers, digital video recorders or even the cigarette lighter itself.
From memory, the fuse for this is rated at 15 amps.
Note also that the heated front seats are wired to the same fuse, and draw approx 5 amps between them.
Pin 3 - Grey / Black to an illumination supply.
On my Cavalier, the ash tray light is powered by an ignition live supply.
So we cannot tap into this, unless you want the gauges lit up whenever the car is running... just like the heater panel does.
If you want light switch controlled illumination, then you will need to tap into a switch illumination wire.
These are grey with a black stripe.
If you want dimmable illumination, then you will need to tap into a grey wire with a green stripe from the fuel computer, instrument panel or the light switch rheostat.
Pin 4 - Brown wire to any good ground or earthing point.
Again, many people cheat and wire directly to the cigarette lighter connector.
Same considerations for currant loading apply as mentioned for the ignition live supply on pin 2
If you do not have an original Calibra connector, you can use a small 4 pin connector from a personal computer.
They do fit.
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