Help with Cruise control

[jkinsey]

I need some help with my cruise control. I have a problem with the switch. I rotate the switch to turn the cruise on, but when I hit the set button, it shuts off. There must be some problem with the switch. Any suggestions? I'm not sure how the stalk comes apart, and I can't find it in the shop manual.
Thanks

 

[steve]

It's very possible the problem isn't the switch. There are two very common problems with the cruise control that could result in what your seeing.

The vacuum hose between the vacuum pump under the cable pulleys that runs to the actuator is split/broken/off.
The rubber contacts for the clutch or brake switches are worn out and don't push the switches in anymore.

The cruise control computer has a diagnostic output and a set of tests you can run to find out what it is unhappy with. The test procedures are in the factory service manual.

Steve

 

[ddavisaf]

Is the Cruise Control the only non-functional unit right now? If your speedometer isn't working either (meaning a faulty VSS, bad cable, or bad reed switch) your cruise control will not engage.

 

[steve]

If your speedometer isn't working either (meaning a faulty VSS reed switch) your cruise control will not engage.

Yes, a bad VSS is number three on the list.

I have a simple page for the Cruise Control on my server.
http://simon.chi.il.us/~steve/Auto/DSM/91_-_94_DSM_Cruise_Control_Diagnosis.html

Steve

 

[jkinsey]

Thanks for the help. I will run through the procedure you listed. To answer your question, everything else is working, including speedometer. The reason I mentioned the switch before is that when I rotate the knob to turn it on, the light comes on. But as soon as I hit the set button, the light shuts off. If it was a vacuum line or even the brake switch, it wouldn't set the cruise speed, but I think the cruise would stay on (the light would stay on). Since the light shuts off immediately, it made me think the switch. I will check the codes though. Thanks again.
Jerry

 

[steve]

The reason I mentioned the switch before is that when I rotate the knob to turn it on, the light comes on. But as soon as I hit the set button, the light shuts off. If it was a vacuum line or even the brake switch, it wouldn't set the cruise speed, but I think the cruise would stay on (the light would stay on).

You would think that's the case but depending on the fault the CC ECU senses it will turn off the light on the control lever.

Steve

 

[jkinsey]

Ok, I'm back to working on this, after finishing up my $1000 heater hose. I'm a little confused. First, while I was doing some "other" work, I noticed that the vacuum hose you mentioned was broken off. I fixed this, but still doesn't work. I ran through the procedure in the service manual. If I run through the Input-Checks, everything comes out ok. I get all of the codes. I am confused on the diagnostic check though. How do I get these codes? The manual is kind of vague. If I plug into the connectors and turn the cruise on, it does the flashing off/on at .5 sec intervals. If I hit the set button, the cruise turns off like I mentioned above. When it is off, no codes are displayed. If I turn it back on, it flashes on/off again. What am I doing wrong? I guess I'm not exactly sure what I am supposed to be doing to get the codes. BTW, I've run the regular diagnostic check for the engine, and I don't get any codes (VSS or anything like that).
Thanks again.

 

[WatchItExplode]

I can't seem to find the section in my factory service manual where it talks about cruise control. Anybody know what section to look in?

 

[danyz250f]

I am in the same boat. Turn the cruise on the orange light comes on but as soon as you hit set the light goes out and the green light never comes back on. When I plug the data logger in and check codes it comes up with nothing even with the cruise light is on. But while driving if I push the clutch in a bit the orange light stays on. But no green dash light or "cruise". I can keep pushing the putton and it stays on but as soon as i release the clutch the orange light goes out. The one clutch wire is un plugged so you can start the car with out pushing in the clutch.

any suggestions

 

[Bone stock]

I'm having the same problem. I've just barely started looking into it, but I'm beginning to suspect the cruise control unit itself. I'll let you all know what I find out (whenever that may be, as I don't have a lot of free time).