cruise control issues

[AKBroncoII]

My cruise control doesn't work. How do I diagnose? Obviously I can't leave the hood up and hang out the window going down the road. Should I replace the vacuum canister deal? It's a manual transmission truck, how do I test the VSS?

 

[85_Ranger4x4]

What year? A BII shouldn't have a VSS.

On my parents '94 Explorer you have to pull the brake pedel up just a little bit for the cruise to work, after 180k it doesn't always get quite all the way back to where it is supposed to be, my dad's '92 GMC does the same thing.

 

[shadetree]

I would start by check all the vacuum hoses. Also, the brake valve as suggested.shady

 

[Jorley]

How is it not working? Pick a number.

Problems:
1. Will not hold proper speed
2. Cruise intermittently cuts out
3. Vehicle surges
4. Cruise control inoperative

Possible causes:
1. Incorrect cable adjustment; Binding throttle linkage; Leaking vacuum servo diaphragm; Leaking vacuum tank; Faulty vacuum or vent valve; Faulty stepper motor; Faulty transducer; Faulty speed sensor; Faulty cruise control module

2. Clutch or brake switch adjustment too tight; Short or open in the cruise control circuit; Faulty transducer; Faulty cruise control module

3. Kinked speedometer cable or casing; Binding throttle linkage; Faulty speed sensor; Faulty cruise control module

4. Blown fuse; Short or open in the cruise control circuit; Faulty brake or clutch switch; Leaking vacuum circuit; Faulty cruise control switch; Faulty stepper motor; Faulty transducer; Faulty speed sensor; Faulty cruise control module

That's the cruise control troubleshooting chart from my 83-90 Chilton's manual. Hope it helps.

 

[Wicked_Sludge]

What year? A BII shouldn't have a VSS.

pretty sure if its got cruise, its got a VSS....

 

[AKBroncoII]

It doesn't do anything. Doesn't work at all. Nothing happens. It's a 91 explorer.

 

[Earl43P]

Does it have a pressure switch on the brake master cylinder? If so, remove its connector and jumper the two pins. That'll rule out one thing pretty quick.

Manual trans will also have a clutch pedal switch that disengages the Cruise at the first bit of clutch pedal movement, unlike the contacts which allow starter engagement, which "make" at the end of pedal travel (bottom).

 

[AKBroncoII]

It is a manual transmission. The clutch pedal does seam like it is down further than it should be.

 

[Earl43P]

On my 2000, it takes just the lightest tap on the clutch pedal to kill the Cruise.

If yours isn't fully up, that would certainly do it.

 

[AKBroncoII]

What would cause it to not come up fully?

 

[Jorley]

The troubleshooting chart I posted is for 83-90 Ranger/Bronco ll, but should give an idea on what to check. Check all the items in step 4.

Here's some wiring diagrams for the cruise control.
http://www.therangerstation.com/tech_library/EDiagrams/files/Diagram_Cruisecontrol_1of2.JPG
http://www.therangerstation.com/tech_library/EDiagrams/files/Diagram_Cruisecontrol_2of2.JPG

 

[Earl43P]

Slave or Master or it could simply need bled.

I'd drive it, lift the pedal fully up with my toe and see if Cruise will engage.

 

[AKBroncoII]

It's sloppy, as in no pressure or anything to hold it up. It's not the slave. Could be the master as it is the only thing that has more than 500 miles on it. Clutch, pressure plate, flywheel and master are all brand new. It was the same with the old stuff in also. The pedal will fall back down anyways. Do you suggest I just hold it up with my foot? Couldn't I just test continuity through the switch with it where it's at?

 

[AKBroncoII]

Looks like it is the clutch switch. Works when I pull up on the clutch pedal. Now I just need to figure out how to fix it.

 

[Wicked_Sludge]

check all the clutch pedal bushings.