cruise control out of control

[usedtowas]

cruise surges bad on my 82 300 sd, any ideas would help?:

[wolf_walker]

Opening your wallet would probibly clear it right up.

Search for cruise. Or surge.

[WannaWagon]

Bump...

...And, not to hijack the thread, but I was going to post about my own cruise problem anyway. I bought my wagon a few weeks ago, and the first time I tried the cruise it worked perfectly. Well, it hasn't worked at all since then. What would cause this?

hi usedtowas,
we also see our share of rust, I got lucky with mine, I took all the linkages apart one at a time, being care full not to mess up there adjustments, cleaned the ends, then put a small dab of grease in the little cups an re-installed. It made the cruz work smoother as well as the fuel pedal alot easier to push.
If that don't fix it do as wolf_walker stated, and if that don't do it guess its time to open ye ol wallet

[bjcsc]

The solution is easy: Just take $500 and set it on fire. It will only take a few minutes to burn up, and you'll save 5 - 10 hours of your time, shipping costs, and much frustration to be exactly where you are now.

[joebiodiesel]

I just installed a Rostra aftermarket electric cruise control in my 300SD. It took a little tuning to prevent it from surging and that's it. It installed in a couple of hours and was pretty easy to wire up with the old cruise module already having most of the needed wiring right there in one place. If you use one, you'll need to know the pulses/mile from the vehicle speed sensor in order to get it working properly. Mine was 4700 ppm, and 90VAC, so I set the sensitivity to Low.
Now I just wish there was such an easy solution for the climate control....

Joe

[wolf_walker]

Originally posted by joebiodiesel
I just installed a Rostra aftermarket electric cruise control in my 300SD. It took a little tuning to prevent it from surging and that's it. It installed in a couple of hours and was pretty easy to wire up with the old cruise module already having most of the needed wiring right there in one place. If you use one, you'll need to know the pulses/mile from the vehicle speed sensor in order to get it working properly. Mine was 4700 ppm, and 90VAC, so I set the sensitivity to Low.
Now I just wish there was such an easy solution for the climate control....

Joe

And I STILL have yet to do a write up on how to wire the stock control stalk into an aftermarket unit. I've been riding around with the knee cover off for months to remind me. This is partly because I'm not sure how to explain it. Might draw a wireing diagram and fax it to someone that can post it. It's cheap and pretty easy.

[vwbuge]

After market cruise is your best option. If not, someone here gave good tips on how to resolder your amp. You can also take your chances and try to find a used actuator.

[WannaWagon]

I found this handy writeup yesterday on diagnosing cruise control problems; it includes instructions for soldering the amp circuit board:

http://www.mbca.org/pages/tech/MBCA_Troubleshooting_cruise_cont.htm

Among other things, it states the importance of using only Osram or Bosch bulbs in the brake lights, because they have a special voltage or something. (I take it this is because they are part of the cruise control wiring circuit for some bizarre reason.) So I checked mine last night and I have the wrong bulb in one of my brake lights.

First question: Could this bulb be causing the intermittent function of my cruise? Have I done any permanent harm by trying to use the cruise with this bulb in the car (I've attempted to activate the cruise maybe only 10 times since buying the car).

Second question: Where can I find Osram or Bosch bulbs other than by mail order?