What environment does the ECU require for the FP (Fuel Pump) output to drop its voltage, causing the relay (controlling the high/low voltage for the fuel pump) to switch to the low voltage ciruit?
When the IGN is on, the relay is tripped and current is passed through a circuit with a 0.7ohm resistor in line, dropping the voltage of the circuit therefore minimising the output of the pump. When the FP lead from the ECU is dropped, the relay switches back and the circuit now carry's the full load to the pump maximising the output.
What I want to know is the what information does the ECU require in order to drop that voltage from the FP output???
MA70 and the Fuel Pump Relay setup
Wed, 08 December 2004 05:00
