Erm... the "relay" unit is the guts of the thing.... the unit is pointless without it.
According to that diagram (which is made for use with a vehicle specific harness)
Gray: Park Brake
White: 02 Sensor
Black: Ground
Then theres the 3 wires from the harness... on the blitz TT's they are:
Red: Constant 12V
Green: Ignition
Blue: Accessories
The Apexi timers are quite cheap... anywhere from $100-150 depending on where you go.
Checkout Autobarn as IIRC they had them pretty cheap (cheaper than most of the online stores)
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