93 sc 300 fuel pump ecu troobleshooting?

[SuperCoupeSC91]

hello, i'm new to this forum, but i have a question, i hope you guys can help me out, this is for my brother, he has a 93 SC 300, his fuel pump doesnt worklike its supposed to, the car wont start, unless we jump it with a jumper wire in the diagnostic port in the engine bay "BP to FP" (Battery power to fuel pump) then the car will run, but without jumping it, it doesnt work, we checked out the fuel pump ecu, but how do we determine if thats it or not ? i assume it is, but my brother is kinda iffy on spending 300$ for a new one since i'm not sure, my brother also said he checked out all the fuses, any help would be most appreciated. Thanks in advance.


*updated*was a faulty ecu..

[Venkatesh]

If this is anything like the Camry, you would want to check:

EFI Main Relay
Fuel Pump Circuit Opening Relay
Starter Relay
Ignition Switch
Fuel Pump Coil Resistance

The Fuel Pump is turned on by the ECM when the EFI Relay and the Fuel Pump Circuit Opening Relays are on. The EFI Relay is turned on when the Ignition Switch is on. The Fuel Pump Circuit Opening Relay is turned on when the Starter Relay is started.

Check the value of the ECM terminal FC, the voltage on the FP pin when the pump is running, and finally the resistance of the fuel pump coil. The fuel pump coil resistance must be between .2 and .3 ohms if the pump is good.

Good luck.