On my 2009 F350 the cruise control won't stay on. The slightest bump and it turns off and I have to push the resume button. It's not the brake pedal/stop light as it will do it with me holding the pedal up. I'm guessing there is a vibration/crash sensor to turn off the cruise control in case of a wreck.

If I'm correct any idea where the little bugger is hiding? If I'm not correct does anyone have any ideas on a solution?

 

Its the switch under the hood on the master cyc

 

Thanks, Ford thinks they are made of gold... Probably just live with it.

 

Bringing up an oldie. I bought a new switch and installed it. Now it's showing a bad switch, Code 0703 which wasn't there before. I'm guessing that is the switch I replaced. I contacted the dealer and they are sending another one (OEM Motorcraft BTW in sealed bag). I double checked the connection and it's solid.

Is there any tricks to putting the new switch in, last one I just unscrewed one and put in the other. Maybe have to fill the little bugger with a drop of brake fluid.

Oh, I threw the old one away so I can't swap it back, dumb move...

 

Update. I got a new switch and checked it. Zero ohms. I removed the one I just put in and checked it. Also zero ohms. It seems the switches are good but I still have the error code P0703.

I have an Insight monitor and it shows the code and says it resets it but when I read it again it's still there. I'm wondering as when I ask for help it shows "Can't touch this". Maybe it's a code it can't reset???

I hauled my trailer this last weekend and now when in tow haul mode if I touch the brake pedal it immediately downshifts instead of going along with the brakes it's trying to stop it with the motor. One time at 55 it downshifted twice when I touched the brakes for a slight traffic slowdown. The tach went up to 3500rpm. That's not good. After that when I had to use the brakes I took it out of T/H mode and all was well. Below abt 35-40 all was ok.

Any ideas this is crazy. The trailer problem just came up after replacing the switch.

 

Going off off of memory when I fixed mine last July....there should be two switches, sounds like you fixed one and the other is still bad. The tow haul sounds like it's working correctly now as the one switch is a pressure transducer that is integrated into the tow haul function of the pcm. The other switch is simply a kill switch and can be temporarily jumped with a wore to see if it works before you order another part.

 

I replaced the cruise control switch which was intermittent. Now the cruise will not come on at all. Prior to this the downshifting in T/H was correct now it's not.

Does anyone know where to get a wiring diagram? In case it's a bad wire connection?

Rethinking this whole scenario. It was intermittent in cutting off the CC when hitting bumps. The switch was replaced, twice. After replacement the CC will not even turn on, much less turn itself off after hitting a bump. Methinks there is a broken/intermittent wire to the CC switch that when the switch was replaced it came apart and now will not let the CC turn on at all. Now to figure out how to get to it to fix it.