Joined the site so I could fix a friends truck. 2004 F-150 2wd 4.6. Truck is acting like a flooded carbed vehicle. Codes I recieved are:

p0191 Fuel rail pressure range performance
p1233 fuel pump driver module off line
p1237 fuel pump secondary circuit fault

By searching your threads I have basically found that it is either going to be the fuel pump gone bad, or the fuel pump driver module. I dont want to replace both and spend all his money. How do I troubleshoot which one it is? If the module is bad, will I still be able to hear the pump kick on, or will a bad module prevent a good pump from turning on?

Any help I would appreciate it, just dont wanna put money where its not needed and we have GOT to get this thing back on the road.

 

Check the fuel pump driver module (FPDM) visually, unplug connector, check pins. The module are made out of aluminum and tend to corrode, split in half, cause problems with circuit board. Usually has a problem when it is wet or humid out. Hope this helps!!

 

Thanks, bought a voltmeter and gonna see if its putting power out. Luckily I have the same truck as my buddy, so I might swap our modules to see if that solves it. A little redneck ingenuity never hurt, well, usually it does, but shouldn't in this case. Unless of course there is a cross in his wiring that blew his module, in which case.............you see where this is going..........two new modules.

 

The one in my truck was so corroded it split in half and the circuit board was exposed!

 

The faults above would indicate to me a bad FPDM. If the FPDM is bad, the pump may or may not turn on, may or may not deliver adequate pressure,.....you see where I'm going?

The driver module is about $90 from Ford. It's a known issue, and has downed many trucks of this vintage.

 

most times the driver module problems and codes are interminent and come and go....like the others said they have problems with the casing corroding away and cracking, most will function properly untill you hit apuddle and get water in one of those cracks, then once it dries out again everything will be seemok till you get more water inside

9 times out of 10 problem is driver module

 

I know this post is older, but I would like to add an EASY and QUICK check that might save the odd Ford truck owner a bit of P1233 FPDM frustration.

The more rugged terrain your truck drives on/thru, the more you will need to check on this wiring harness...

https://www.f150forum.com/f4/p1233-fuel-pump-driver-module-off-line-84974/#post2312574