The trouble I had with mine is that I didn't have the original wiring loom so I had to make my own, although I used mainly the same colours as the original loom, my loom is not exactly as the original.

Using the photo (and numbered pins) from my original reply, the wiring is as follows:

[Connector 3]:
Pin #1: +VE, alarm LED
Pin #2: +VE, water injection
Pin #3: -VE, alarm LED
Pin #4: -VE, water injection

[Connector 4]:
Pin #5: Not used
Pin #6: Not used
Pin #7: Not used
Pin #8: Not used

[Connector 2]:
Not shown on photo but connector is for the two control buttons

[Connector 1]:
Pin #9: -VE: ECU Pin #1 (black)
Pin #10: +VE: ECU Pin #20 (red)
Pin #11: Not used (n/a)
Pin #12: Switched Ingnition +VE: ECU Pin #25 (orange)
Pin #13: TPS: ECU Pin #17 (green)
Pin #14: Coolant Sensor: ECU Pin #29 (blue)
Pin #15: ACT Sensor: ECU Pin #31 (yellow)
Pin #16: MAP Sensor: ECU Pin #15 (white)

Wire colours are in brackets, although as I say, I made my own loom so wire colours may not be identical to the original loom but as far as I remember they followed the original colour scheme quite closely.