Cruise control working intermittently

[SFAdad]

I changed the stop switch on the master cylinder back in '10 after reading about a similar problem on this site. It worked for a couple years but recently the problem returned. Yesterday I installed a new Motorcraft switch but it didn't fix the problem.

Sometimes it will come on when the start button is pressed only to turn off by itself. When it quits on its own resume will not start it back. I'll press the on and off switches a few times then it will come back on but stop again. Other times it will stay on for several miles and not turn off until I press on the brake.

Since replacing the switch didn't solve the problem could it be the plug?

2003 Explorer

 

[gamenerd]

I'm having the same problem with my 2002 Explorer XLT V8......the cruise control works literally whenever it wants....i haven't changed anything but im pretty sure im heading your route soon. im currently replacing a piston and bent valve from cylinder #8 and having a hard time finding walkthrough with pictures.

goodluck

 

[N1265]

Every time I have trouble with my CC I :

1) take the switch off the master cylinder and hose it down with carb cleaner and then WD-40
( this includes the hole where it screws into )

2) If that don't work, I take apart the brake light switch on the brake pedal
( a PIA to get to for larger guys ) and clean / WD-40 the brake light switch contacts.

Here is a link that talks about replacing / cleaning the brake pedal switch.

http://www.explorerforum.com/forums//showthread.php?t=263098&page=2


for me, it has always been one of these two things...

 

[SFAdad]

Thanks. I'll crawl under the dash this weekend.

 

[im faster]

Just replace the sensor on the master cyl.

 

[pet575]

Not sure if you have ABS, but mine quit working due to a bad wheel bearing causing the ABS sensor to misbehave. When I replaced it I found the ABS sensor wiring had been compromised and was likely shorting out.

CC would never work with that going on so if you have ABS I'd check your connections.

 

[SFAdad]

I installed a new sensor on the master cylinder last weekend but it didn't solve the problem.

Wouldn't the ABS light come on if there where sensor problems? I replaced the ABS sensor on the rear differential a couple years back due to the light coming on and staying on but it hasn't come on since.

The Haynes cruise control schematic shows a redundant switch on the brake pedal that's in addition to the brake light switch on '03 models. I'll check under the dash this weekend.