I have read numerous threads and unfortunately not able to fix this. What I've done is replaced the speed sensor located on the rear differential. Also replaced both ABS front sensors and VSS sensor located on top of transmission. All sensors are oem. In addition also traced all wires for continuity and appear to be in excellent condition. CODE...speed sensor A fault. Any input on this would be greatly appreciated. Thanks.

 

Exactly which code do you have? Your description doesn't give me enough information. I need the code number.

When you say you traced the wires, did you check them electrically for continuity and for shorts?

It would also help a lot if I knew what year and engine you have.

 

I checked for continuity and loose connections. Code P0500. Do you think resetting the ECU by a ford dealer could possibly correct this code issue?

 

No.

What year, model, transmission, drive train, etc??? We are not psychic.

 

Vehicle description: 2005 F-Super Duty Lariat FX4
Body Style: Crew Cab
Engine: 5.4L 3V V8
Fuel Type: Gasoline
Transmission: 5R110W 5 Speed Auto Trans NAAO
Drive Type: 4 WHL L/H Part time drive
Axle Ratio: 4.10 Ratio
Axle Code: 4N

 

Have you specifically scanned the ABS system for any indicated faults? It has to be working correctly in order to supply valid VSS data to the PCM and cluster.

 

I have not performed a ABS specific scan but scanned with a OBD 2 scanner. Tried multiple scanners at different price points and they all come up with same code P0500 Speed sensor A. Looks like i might have to head to dealer and get this vehicle professionally scanned.

 

I thought the VSS sensor was on the rear differential pumpkin?

 

I know for certain that it will not fix the problem.

 

Try forscan. It is available free at www.forscan.org. You'll need an ELM327 adapter that is under $30. I bought mine on Amazon. This will read all the codes in all of the modules on your truck.

 

Just a thought...
Metal debris in the rear diff can cause false faulty ABS sensor problems. Solution is to remove the diff cover, clear and refill with new oil.
Sensor cracks can happen with replacement and faulty cable connections to the rear diff sensor can also cause ABS rear diff sensor failures.

 

You do do not know WHY the ABS system has faulted, you're only guessing. Getting the thing scanned properly eliminates a lot of guesswork and allows for an actual focused troubleshooting effort instead of stabs in the semi-dark.

 

If I new why the code was there I wouldn't be asking or shooting in the dark. I'm simply trying to figure it out. Thank you for your time. I know that at any time I could bring it to the dealer....that I do know.....