interestingly, although the wiring diagram clearly shows that the main relay solenoid power comes direct from the ignition via a diode, and then direct to earth, and the fuel pump relay earth goes direct to the ecu, not having the main relay solenoid plugged in means the fuel pump relay has no earth from the ecu.
Short circuiting the main relay solenoid means the fuel pump runs when the ignirion is switched OFF not when switched on.
However, having the main relay plugged in, the fuel pump primes as normal.
There is certainly some strange wiring in this car, even though its completely normal and standard, it doesnt do what you would expect according to the wiring diagram!!!
Goes to show though, the main relay really is critical to the running of the car, it doesnt just switch sensors on, it completes the fuel pump relay circuit too!!!
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