I hope this is the right place for this thread, sorry if not. My Ranger is a 2005, 2.3L, 2wd.

Started with the engine losing power when I was driving, followed by it completely losing power. It will crank, but won't start. After some trouble shooting, the fuel pump, the two fuel lines from the fuel pump to the fuel filter, and the fuel filter itself were all replaced with new ones. Still no start.

Spraying starting fluid into the air intake, it starts. So, a fuel problem? In a stroke of genius, my bother used a code reader to get a direction to go with. The error we got was a p0232. Ok. Well, we checked the fuse for the fuel pump and PCM. All good. He checked the voltage on the inertia switch harness and the fuel pump. All good. So we replaced the inertia switch with high hopes. Again, crank but no start.

We cleared the codes and checked again, p0232 still comes up. There does not seem to be a electric iusse both of us can see and fuel does reach the fuel rail under pressure since the beelder valve has good pressure behind it. Both of us are a bit frustrated, is there something we are missing? I hope you guys can point us in the right direction.

 

Welcome to the forum

Its good to post the code number but also the definition you are using
P0232 Fuel Pump Secondary Circuit High

Secondary circuit in this code means the computer is seeing 12volts to fuel pump when there should be NO volts to fuel pump

When you turn on the key you should HEAR the fuel pump run for 2 seconds only, a HUMMMM from the tank, but just for 2 seconds
This is a safety feature
The computer activates the Fuel Pump Relay in the engine fuse box for 2 seconds when key is turned on, then deactivates the relay after 2 seconds, if computer still "sees" the 12volts after it deactivates relay then code P0232

So locate FP relay in engine bay fuse box and pull it out, test for 12volts at inertia switch again
Should be 0 volts of course
Now key OFF, plug back in the FP relay and test for 12v again, if it has 12v then relay is bad

If still 0volt then turn key on and you will see 12v but for just 2 seconds then it should drop to 5-8volts, thats the monitor circuit volts no amps so pump would be off and computer would see 0volts
If 12v stays on after 2 seconds then replace relay

I am showing relay 46A as fuel pump relay, and 46B as windshield washer relay, these should be swappable

The reason it won't start is because if there was an accident and a fuel line broke the fuel pump would just keep on running, perhaps feeding a FIRE, thats the safety feature, computer will only run fuel pump for 2 seconds when RPMs are under 400, when engine starts it would then power fuel pump full time
If computer can't shut off fuel pump power, via the relay, then vehicle is unsafe to drive



One other thing that can happen that prevents start up is a shorted TPS(throttle position sensor)
The TPS has a 3 wire connector, unplug it and see if engine starts, if so you can drive it but just to the store to get another TPS, lol, MotorCraft it possible, Hitachi if not
But nothing to do with P0232

 

Thank you for the reply, and sorry about that. Didn't dawn on me to post the description as well.

We have tested the inertia switch before using the method you have posted. Again, it didn't dawn on me to fully explain that either. On re-testing this morning, it reads 0v on off, then reads 11.6v (close enough?) on turn, then drops.to 6.5v after words just like the first test we did. We also tested the fuel pump harness, unlike our last test however, the fuel pump now reads a constant 10.5v with the key in the ON postion. Which is strange since it didn't read that before today.

We also tested the relays under the hood by switching both 46(A) fuel pump relay and 46(B) washer pump relay. Then turning on the windshield sprayers. Both fuses work.

I also checked the TPS(throttle position sensor) as you have suggested. I unplugged it and tried starting. It will sort of crank, but stop dead. Thanks for the tip, worth the shot though.

My bother is the more mechanical experienced here, by far. After testing and talking to another experienced person, he believes that the PCM is the fault here.


Edit: Forgot to mention, the fuel pump can be heard starting for about two seconds. If that matters in this case.

 

The inertia switch should have a pink/black stripe wire, its runs back to the fuel pump

The Dark Green/yellow wire is from FP Relay and also runs to PCM pin 40, FP Monitor circuit

Inertia switch can show lower than battery volts if pump is working, it draws amps when its on, and the 6v is correct for monitor circuit after the 2 second run time

Not sure how fuel pump wires at the pump can read 10v but you don't see that at the pink or green wires
FP Ground at the tank is a plain Black wire
Black/white wire is the ground for fuel level sender