There is a long thread about ABS "lockup" issues and deals with Forscan and placing the ABS unit is "service mode"
https://www.fordownersclub.com/forums/topic/137837-abs-module/
The short end of this is they may have to replace the ABS unit because it has a bad = faulty solenoid that causes the unit to "lock up" one of the brakes on one wheel due to that faulty sticking solenoid or module - it thinks the system is in a skid and placed the wheel in a type of lockdown to try and reduce the skid.
However, this may also go back to a sensor on a wheel that is not working right. This may not be the fault of the ABS, but the ABS unit is doing this because as you drive the wheel speed sensor is not sending the right signal or "tone" to the system - so it thinks it's in a skid and because of no-tone or "bad tone" from a sensor - the ABS system tries to protect the vehicle by locking up the
opposite wheel - so it's something to look for and investigate.
- To possibly help in the diagnosis: Check your dashboard for the ABS light to blink on when you apply the brakes firmly - it also may try to engage the ABS system. You can feel the pedal pulsate - and you may also hear a metallic "BRAAAA-AP" and ring noise - it indicates the ABS system is engaging because it thinks the vehicle is in a skid and it "sees" a sensor telling it one wheel is locking up.
- IT would also pull to one side to show the wheel on that side is affected by this.
So the right front/rear left wheel pairing which is also a part of the master cylinder piston arrangement - may need to have the push-rod for the brakes to be checked - see if a switch plunger is fallen out of it's holster in the brake pedal assembly. It may be the pedal is not able to retract fully to release the fluid back into the top tank reservoir and depressurize the system because something is blocking the pedal from retracting.
The lines to the brake cylinder or the caliper are from the ABS unit - but they may not be able to release pressure so you'll have to release the brake by having to remove the pressure by loosening the bleeder nipple on the caliper or wheel cylinder just so you can move the vehicle. So if you find the wheel that is locking - the speed sensor to that wheel and it's opposite side and kitty-corner opposite - those sensors may need to be checked for dirt or age too - see if they can be removed, cleaned and replaced - see if that action can help clear this code. Their harness too - see if it's been damaged or nicked by debris.
The codes will only clear when FORD uses their scan tool (J2534 and their software) to force the ABS unit in a diagnostic mode to clear the codes stored previously.
The codes will clear (asterisked in FORscan) but will always remain in the system because of the previous vehicle that caused this - and it's VIN code - will always be "reserved" in your vehicle. For it's VIN ID does not match the vehicle so it may also be unable to clear because the previous vehicle may have come from a different TRIM line - SE versus S or Platinum (SES) which their systems handle ABS and it's communication differently.
