I need help with 1999 F350 superduty 4x4. I keep getting a DTC P0230 Primary fuel pump circuit failure . I need a wiring diagram for this circuit I don't believe it has a relay(or does it?) anyone know?
Any help would be appreciated

 

It should have a relay. The current draw is a little more than what runs through the PCM. I am not so sure about diesels, but if you have a gas motor, you have a return fuel system. I'd suspect your FP relay to be under the hood, you can check for voltage across the coil connections and voltage on the input/output connections. However if the engine is running, the coil should be energized and passing current.

 

WELCOME to FTE!

What engine do you have?

 

Thanks for the replies! Its a 1999 Superduty 7.3 Turbo Diesel 4X4
I finally found the relay .There's a small relay block under dash behind the stereo I used diagram to figure out that I had no key on power. Traced the wire back through firewall and found it broke under hood . Repaired wire and it is up and running great!