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Ironmike, Ford Technician
Category: Ford
Satisfied Customers: 3385
Experience:  30 years ASE Master tech L1 . Ford master
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Ford F250: 1999 F250 v10 DTC code P0500. Father-in-laws truck

Customer Question

1999 F250 v10 DTC code P0500. Father-in-laws truck I have not driven it. Runs fine for a few minutes then very rough "like driving over coblestones" and then dies. Restarts and runs for a few minutes and does the same. ABS light does not appear to be on (need to verify). I was going to replace the VSS on rear diff but if ABS light is not on I don't think it is that sensor. Are the input and output VSS on transmission accessible without dropping the tranny? I also do not know if the speedometer is working correctly when driven either. The truck is a two hour roundtrip drive for me so I would like a list of things to check before i make the trip.
Submitted: 9 months ago.
Category: Ford
Expert:  Ironmike replied 9 months ago.


what engine and how many miles? any other codes?

Expert:  Ironmike replied 9 months ago.

check the code again. Rear differential speed sensor or a wiring fault should not cause a stall.

Customer: replied 9 months ago.
I did not think so but could a P0500 fault also be the input or output speed sensor on the transmission? In other words is the P0500 fault limited to the sensor on the diff or could it be one of the tranny sensors witch could have the transmission shifting weird and making the vibration?
Expert:  Ironmike replied 9 months ago.

is this gas or diesel?

Customer: replied 9 months ago.
gas V10*****
Expert:  Ironmike replied 9 months ago.

The sensors on the trans are input and output speed sensors and they would set a different code. Can you check the ABS module for codes or make sure it communicates? Does the ABS light come on when the key is turned on?

Expert:  Ironmike replied 9 months ago.

very common for the rear differential sensor to fail or even the harness to get damaged. I am not sure how this is connected to the stalling.

Expert:  Ironmike replied 9 months ago.

input and output speed sensors are on top of trans and accessible from the outside.

Customer: replied 9 months ago.
Have you replaced them before? Is it extremely difficult to reach them on top of the tranny? Any special tools required? Also since the P0500 is a general fault code would a better code reader give more specific codes as to which sensor is bad?
Expert:  Ironmike replied 9 months ago.

Yes, but like I said the codes would be different. p0715 or p0720. I would rather see live data to confirm be for replacing sensors. you can ohm out the rear differential sensor. most of the time I have seen them open or really high when ohmed

Customer: replied 9 months ago.
Sorry, I missed one of your response above. My reader would not pull ABS codes and I am not sure the light is on or off. I guess I need to make another trip and drive it for my self and get a better reader. The rear diff sensor is cheap and easy to replace so I will start there.
Customer: replied 9 months ago.
can we keep this open till I have a chance to drive the vehicle and change the diff sensor? Will I be able to continue the conversation ? Not sure how the justanswer site works.
Expert:  Ironmike replied 9 months ago.

yes, we can keep this open as long as needed. The rear differential sensor is usually not hard to replace.

Customer: replied 9 months ago.
Thanks Mike. I will respond is a couple days after I change the sensor.
Expert:  Ironmike replied 9 months ago.

ok, great and good luck

Customer: replied 9 months ago.
Mike, I reread the codes and P0231 now comes up "Fuel Pump secondary circuit low voltage". I swapped the relay with a good relay and the truck would still not start.Phil
Expert:  Ironmike replied 9 months ago.

we need to check power to the fuel pump and then fuel pressure if the pump works. It could be a bad fuel pump. Best to check power at the fuel pump with key on and pump energized.

Expert:  Ironmike replied 9 months ago.

good idea to swap relays

Customer: replied 9 months ago.
Mike,I can figure out how to get the fuel pressure gauge on the fuel rail but how is the easiest way to check the voltage at the pump? Looks like the wiring harness runs along the the frame above the tank.Phil
Expert:  Ironmike replied 9 months ago.

yes, there will be a connector you can back probe. They make probes for multi meters but you can use a paper clip, just make sure it is not touching ground

Customer: replied 8 months ago.
Mike,I replaced the fuel pump and the engine still chugs a few time and dies. I should have check the voltage at the tank when I had the tank dropped. Is there another way to check the pump voltage? The plug is inside the frame and is not accessible without dropping the tank.Phil
Expert:  Ironmike replied 8 months ago.

how about fuel pressure? we can check power at the inertia switch.