trailer brake control issues/ cruise control

[noxided]

my cruise control does not work and my trailer brake control is not working at the same rate i am applying the brakes anymore.

tested on another 6.4 and the trailer brakes worked ok.

Im assuming it the controller

with the brake pressure switch cause this?

[aclem16]

The most common cause of cruise control being inoperative is DTC P0703(Brake Switch B Input).This DTC is caused by a faulty cruise deactivation switch which is located on the outboard end of the master cylinder.You may have 2 separate problems or it could be caused a brake switch.I would check the PCM for DTC's and if P0703 is stored I would replace the switch on the master cylinder and clear DTC's and then check your cruise and TBC.Good Luck.

[713Diesel]

I believe that someone said that if the switch on the master cylinder is bad something would be wrong with you brake lights also........ Not sure if this is true as I have not had the problem.

[aclem16]

There are 3 brake switches total.2 on the master cylinder and one near the brake pedal.The outer one on the master cylinder is the cruise deactivation switch and when it doesn't agree with the one mounted near the pedal,the cruise control is disabled.I work at a Ford dealer and a I assure you that when the deactivation switch goes bad,it doesn't affect the brake lamps.Go to your local Ford dealer and ask for a 9F924.You may have to have DTC's cleared once it's installed.Trust me,I replace at least 3 of these a week for cruise inop.