PLEASE HELP

[Mr tints]

just bought a cup 172, for 500 quid, now yes its cheap, but now i know why, it wont start, the ecu wont power up, so i need a wiring diagram for the engine ecu, to trace a wire back as its deffo an immobiliser fault, the car will crank for about 5 secs then goes off, relays under the bonnet are all ok, apparentyly pins 1 and 3 on the relays should be 12v, pin 3 is at 4v, so im thinking wiring fault, checked all wiring loom right back to the bulk head but am yet to remove the big rubber boot which im guessing contains a block connector, had a wiggle of the wires round there and the wipers set off so im guessing thats where the fault lies, can anyone help me with this,

also heard of an immobiliser reset procedure where you press the clutch hold the wiper stalk and turn the key?? is this correct?

thanks in advance
john