Just say the Injection ECU [ black] has to have live 12v on pin "1" of the 25 pins, to identify pin 1....you will see a longer line of pins....ie...1 to 13 and a shorter line 14 to 25...so pin 1 right up the end [ sorry cant remember which end ]. Remember the "Bosch KE" system will run without the supply to pin "1"...but will be a nightmare to start from Cold, as the ECU keeps control of the IMPOTANT Pressure actuator etc, ECU has NO control of the Fuel Pump / Relay / fast idle valve/ or Cold start 5th injector, hence car bursts into life.