Cruise Control Woes...

[TurboPh1sh]

Hello everyone!

I have had my 1998 XLT 5.0 explorer for a while now and have used this forum's knowledge base for many issues that I have been able to resolve myself thankfully... well unfortunately, I have hit a dead end with my cruise control. I have looked through as many cruise control threads as i can and cannot find anyone with a similar issue as me.

I bought my explorer with damaged cruise control switches so I assumed they weren't working (torn, holes, cracks, lights not working) but I replaced the switches and the harness they came with and only the passenger side controls light up and the drivers dont. No lights come on the dash at all either. It almost seems like the switch on the driver side is bad, but its brand new.

Cruise control doesn't work. No ABS light, no leaky switch on the Master cylinder, no blown fuses, no issues with the brake lights.


Is there anything Im missing?

Thanks so much guys!

 

[llamaking122]

on older fords it was controlled by a vacuum so it may be you have a vacuum leak

 

[obie]

With the 5.0 there is a cable running from the throttle body (where the throttle cable linkage goes to) to the cruise control servo, located on the passengers side rear inner fender/firewall area. I'd run out to my explorer to take a better picture, but I don't have it right now, haha. It's right by the heater box though. Anyways, check to make sure that your cable is hooked into it before you start checking wiring. It could be a bad switch though, sometimes even brand new parts are bad. And I assumed you've tried it at highway speed? If I remember right, cruise won't engage below 35mph.

If none of that helps, you might need to track down a wiring diagram. You can always go to http://www.motorcraftservice.com/vdirs/retail/default.asp and pay twenty bucks or so for a one month subscription, and they'll even have troubleshooting guides for a lot of electrical/mechanical stuff too.

Edit: It would help if I attached the picture. Oops!

 

[vroomzoomboom]

if your horn does not work along with the cruise, there is a 10 or 15 amp fuse under the hood that everyone overlooks. check it out and see if its blown.

 

[rollinstone]

I had a similar problem...tried all kinds of things. Eventually I came across an article that mentioned an upgraded cruise control shut off wire for 2nd Gen Ex's from the brake master cylinder. I forget the exact name of the wire, but if you go into your Ford parts dealer they can pull it up for you. I think it was $20 or so. Did the trick! Never had a problem since.

 

[TurboPh1sh]

Thanks for the tips guys! But I have had some developments!

So the other night I was waiting for my 'Ploder to warm up and I thought to myself that I should wack the cruise control buttons to see if they light up...

Well whatdaya know, I do that and the driver side lights up!

Now I am able to run through the cruise control diagnostic and it comes up with 2 blinks... BPP (brake Position Pedal) switch is bad.

Is this easy to replace?

Also, for what its worth, I found some articles that link the BPP switch to the Shift interlock solenoid... Ever since I can remember having my truck I was always able to FREELY move the gear shifter from P to D without applying the brake pedal... Could these issues be linked?!

Thanks for all your inputs guys!!!

 

[Turdle]

Yes, they are linked. Take a look-see at the brake pedal assembly--there should be a dual function switch on the bracket. It might just be shifted out of it's holding tabs--

 

[TurboPh1sh]

Update:

I found a wiring diagram and was able to test all electrical connections to the cruise control servo and everything checks out good. Even the connection from the brake position switch.

I found that during the cruise control diagnostic test the CC servo is supposed to completely pull the throttle cable so you can check for connection/binding. My servo doesn't respond or move. Not even a hum.

I performed the same diagnostic test on a 2001 f-150 and the servo did its test just fine. Now im thinking the servo or the little computer that is attached to the servo is bad...

Now I need to go out and find a servo. Looking at the servo it seems that it is part specific. It says explorer 5.0 LHD. awesome... No parts store sells new ones.

 

[Chikar]

I wouldn't be in a big hurry to spend money on a servo just yet.

With the connector at the servo unplugged, you need less than 5 ohms resistance from pin 4 (tan/lt blue stripe) at the servo connector to pin 1 at the BPP switch. Any higher and it could make the electronics in the servo think the brakes are applied so, no cruise. Pin 4 of the servo connector needs to be at ground through the switch.

I had the same problem, replaced the BPP switch and cruise worked. I also changed the steering wheel switches because the bulbs were burned out.

Then the Explorer started messing with my mind!!

Soon after the cruise quit again. Testing showed the Deactivation Switch on the front of the master cylinder was bad, resistance triple the max 5 ohms. The cruise worked after replacing it, for a whole 10 days. Testing showed the new Deactivation Switch was bad which I didn't believe and wasted a lot of time convincing myself it really was a bad NEW switch. Changed it again and cruise has been fine for months.

I'd be very suspicious of your BPP switch if your cruise doesn't work AND you can shift into gear without stepping on the brake.

 

[TurboPh1sh]

I know I am resurrecting my own thread but I figured I would update it with the fix.

Turns out the BPP switch was just in the right resistance range to not light the brake lights up without the pedal depressed but enough to kill the cruise control switch.

I bought a new BPP switch and that fixed my issue. Cruise control works now!

If I remember correctly I was reading 9 ohms of resistance or something like that.