2003 ford expedition 4.6 Cruise control wont lock in

[comtecjon]

Hello, I have a 2003 ford expedition 4.6 98k miles, cruise control wont set. I've replaced all buttons, brake cut off switch, Passes all tests servo static test good, kicks throttle, I have no idea what to do next.

 

[Hamfisted]

So when you're cruising down the highway, you hit the ON button then the SET button, does the little green icon light up on the instrument cluster ? It's just not grabbing and maintaining the speed you select ? But when you are parked and run through the speed control switch test you do hear it actuate the throttle ?




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[comtecjon]

I hit on while driving, and set, no green sync lite. when in park no run, I do speed contol switch test, I do hear it actate the throttle.

thank you for responding this thing is driving me nuts..

 

[comtecjon]

Any Idea what to try next?

 

[Hamfisted]

Doing the button test do you get the green icon on the instrument cluster responding to the buttons pressed ?


Gen2 Cruise Control Circuit Wiring Diagram


Cruise Control Repair and Diagnostics

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[comtecjon]

Hi
Yes it's always passed all button tests after i replaced them, then throttle kicks. still wouldn't lock in cruise control. I replaced bpp switch now it fails 2 flashes at the end of test. If i apply the brake a few times then it will pass and kick. indicates bad bpp switch. so I replaced it again now it fails same way auto fail 2 flashes at the end of test, apply brake a couple times, then test will pass. did I put the bpp switch in wrong? I saw a post where he had to lift the break pedal to put switch in? I should have left the original bpp switch in it passed every time but wouldn't sync cruise control.