Dear all.

I picked up an early 95 993 a few weeks ago and later discovered that the cruise control would not set I checked the fuses and all seams fine there but has anyone had any issues or have any ideas to diagnose.

Thanks

 

I had trouble with this once on the highway. I shut down the engine (while coasting, empty highway) and pulled out the key and started up again. Worked fine after. Likely not your problem if yours is consistent. Used CC units on eBay aren't that too expensive.

 

I have a cc unit forsale. Pm me

 

Make sure your clutch pedal is coming all the way up, that was a problem mine had when I first got it.

 

You should be able to see the switch on the pedal cluster pretty easily if you remove the wooden board. Perhaps it's out of adjustment or not working?

 

Me too, same thing!
Gordo

 

Having same issue. When I hit the stalk to engage it immediately begins to accelerate. I don't mind but the cops do. Acceleration is done by holding stalk in same direction. Any thoughts or experience with this?

 

I believe that if you press the clutch petal while the CC is on, the car will coast for about 20 or 30 seconds then the engine revs. I did this once coming up to a red light about a mile away, I was surprised that it revved and it stopped once I taped the brake. I figured CC was why. I think the brake petal and CC cancel are the only ways to disengage it.

 

99% of the time this is the root cause. The switch just needs adjustment.

 

ALL brake lights must be intact, halogen even. LED brake light bulbs, due to their minimum voltage drop, 1.2 volts, will disable CC.

 

That would make sense if the OP couldn't disable the CC by pressing the brake, but thats not the problem. If he isn't stepping on the brake there isn't any current going to the brake light and therefore no voltage drop.

 

Sorry yours isn't working. I just used the cruise control for the first time this week and mine worked perfectly and I'm impressed with the accuracy for a manual and the ability to shift while it is engaged. Once you get yours sorted, it works well.

 

I don't think that's right, according to post #4 in this thread

I'm still trying to translate this... could it be that a circuit in CC unit is grounded through the brake light circuit and that ground is interrupted when the lights activate? Perhaps this is some kind of belt-and-suspenders fallback to disable the CC unit if the pedal switch malfunctions.

 

CC has a low "keep-alive" voltage/current supply to the brake light circuit, if there is no bulb load the CC "sees" the brakes being used.

 

Indeed, I am all sorts of jacked up about this. I agree with the brake light arguement now. Furthermore, if you press the clutch petal you will disengage the CC. It turns out what I did to make my engine rev was to shift into neutral without stepping on the clutch. I had a few hours of driving today to experiment with that.