Cruise Control Won't Set ... ?
 

So I pick the car up from the MB Dealer today while it was in for service and I'm coming back home, go to set the cruise at 70mph and all of the lines on the speedo from 70 to the max speed flash and it won't set the cruise. It isn't the flashing dashes on the center screen readout, this is the actual lit lines on the speedo that are normally always illuminated. Later in the day I got it to set at 40mph in town but there was a lot of traffic and I couldn't see if it was actually working to maintain the correct speed (but it appeared to set by un-illuminating all the speedo tracer lines up to 40mph. I did it a couple more times at speeds between 30-50 and it appeared to set but went off once and doesn't seem to set at higher speeds ... very weird. Any suggestions?

did you make any tire/wheel size changes recently?

About 3 months ago I did change to 19" wheels/tires but tried to stick with as close to stock fitment as possible... tires are 275/35/19 rears and 245/40/19 fronts.

hmm, seems safely within the allowable differential, ie only .4" per rotation.

i was thinking that the computer was having difficulty reconciling the different
rotation speeds between front and rear but this doesn't seem likely given your
specs. cruise module on the blink? had dealer looked at it yet?

I had the same problem, after alignment done cruise-control works again

HELP - 2000 s500 Cruise Control Problem
 

Hi,

I recently changed my wheels to a 19" and ever since then my cruise won't set above 70km. If I try to set it above 70km the cruise bars in the instrument cluster flashe for a few secs then stop. I have the alignment done however still not solved. PLEASE ADVISE

Cruiese control problem
 

Know this is very old post but maybe be work for someone.

I had some other problem to reset the whole system i removed the battery once i reached my office. In afternoon i put the battery on and start driving. when i tried to set cruise on 140 KMH the same problem occurred.

Remedy

Switch the engine. Turn on and off the ignition three times, remember no start. and system reset to normal. I think you have to do this with hard reset every time. As i have to do it.

Regards

Thanks for the tip

Could you clarify this a bit, please?

Step 1: "Switch the engine"? Do you mean switch it on or off?
Step 2: "Turn on and off the ignition three times, remember no start." I understand this part.

Do you mean to start the process after leaving the battery disconnected for a short time and then reconnecting it or can you start with Step 1 without disconnecting the battery?

Thank you!

maybe different tire sizes ?

I just put slightly larger tires on the back of my S430 than the front. Ever since then, I've had the same cruise control problem. Is there anything I can do to fix it without going back to stock tire size?