Cruise control again

[Jassper]

Hello everyone,

this is an everlasting topic and will be I am certain of that. Anyhow - this is what I found about my CC:

Symptoms : works most of the time, engages after 2 seconds after being set. It has always done so. I noticed my father's W210 CC engages instantly with no delay. I consider this 2 second delay normal.

Question : how long does a working CC take to engage on a W124 diesel?

CC has had a long history of symptoms : they began when I pulled the actuator upwards - to speed up. CC would cut off and would refuse to work unless the ignition was switched off and on.

Sometimes it wouldn't work even after turning the ignition on/off. Always after some time it would work again. Sometimes with CC engaged I would drive over a slight bump on the road - noticeable but not too much. CC would disengage and would not want to engage anymore. Again, after a few hours it would.

Now the situation is that it engages fine, I can speed up pulling the lever up but when I slow down (lever down) CC will cut out and would not work anymore unless being reset (ignition off and on).

I have taken apart the motor on the engine block (that pulls the gas bowden), cleaned it inside (and successfully put all parts back into it) but the symptoms are the same. So, no motor.

I have taken the CC amplifier out and re-soldered each and every contact. No change.

There is a box at one side of the amplifier (007 545 54 32). I thought it was a relay box. I took it apart to clean the contacts but there is no relay inside - only 5 or 6 resistors on a circuitry board. That is all. I re-soldered them all. No change.

I also suspected the Hall sensor at the speedometer's side but now thinking of it - CC works fine, speeds up when I want it to and keeps desired speed I have concluded the following :

1. The Hall sensor is good - otherwise CC wouldn't work at all or act erratically and not keep a set speed

2. The motor is also good - to keep a set speed it must turn left and right to speed up and slow down

3. It must be the amplifier - because CC quits work when I slow down by pulling the lever down but otherwise works great. Must be either an electrical or logical problem. After having re-soldered everything I ruled out cracks. I think it must be a faulty component on the amplifier board. Now - which one? I have no idea.

Question : are there any other components to cruise control I have overlooked to look at?

I checked for the price of a new amplifier (005 545 05 32) - it was $645. I don't think I need it that urgently - especially when it works (just don't pull the lever down). I wonder what happens next. What is the price refurbished amplifiers come at?

.

[Rick Miley]

http://www.gdl-online.com

[95300YDT-A]

Dear Jassper,

One of the other members is the man you need.
I read once a thread of him about this topic and I remember he opened up
the CC servo to repair it.
So I sugest a search on the name of "Tasma" and it will lead you right to that thread. I am sure he could help you out!
Good luck,

Danny

[Jassper]

Originally posted by 95300YDT-A
[B]Dear Jassper,

One of the other members is the man you need.
I read once a thread of him about this topic and I remember he opened up
the CC servo to repair it.

Hello Danny,

thanks for your suggestion but I also had the servo removed and opened last summer. It was in mint condition inside. I think it is the amplifier. Unless, of course, it is not. I'll have it exchanged with a rebuilt one and will let you know of the result.

.

[wolf_walker]

Probably the cruise control amplifier.

The trouble with these darn things is A: the contacts crap out after a number of years. and B: there driving an motor off transistors, high technology for the day, and it was a bad idea then and is a bad idea now. Those things die often from over amp draw on a worn actuator. There needs to be a relay to bear the amp load in the system, not those transistors. Than and perhaps a vibration absorbing mount and I think the life expectancy and reliability would increase a good deal.

I'm toying with the relay idea, I think I could build it. Cheap parts, just time intensive.

[Bob300sdl]

Jassper, I have done a lot of homework on the replacement of the cruise amplifiers.

A new one for my 1987 300sdl was $395.00 rebuilt one's range from $195.00 to $249.00.

The good news is I found a fellow in Oak Ridge, TN Company's name is Performance Analysis Company Phone # 865-482-9175 Ask for George Murphy E-Mail 76620.2133@compuserve.com
The cost for my amplifier was $149.00.

They only specialize in Mercedes Electronics.
I just came back from Florida and the trip down there and back, the cruise worked better than new, especially through the mountains.

Good Luck Bob


.

[300SDog]

Other option might be junking the ridiculous stock MB/CC system entirely.....

There's gotta be discreet American made after-market product that can replace the entire thing for less than $150 with superior components that work better.

These are outstanding cars for their longevity, reliability and handling....

But stuff like the Cruise and Climate control are outright crap apparently designed by crackpot engineers whom Mercedes Benz keeps locked in the basement.

.

[The Warden]

Originally posted by 240DieselDog
Other option might be junking the ridiculous stock MB/CC system entirely.....

There's gotta be discreet American made after-market product that can replace the entire thing for less than $150 with superior components that work better.

That actually seems logical to me; as much as i like things to remain factory, it seems like the M-B CC setup's prone to issues.

I think that it's GDL who said that an M-B amp and actuator are good for about 50K miles of actual use, which appalled me and partially led to me not wanting to spend the $$ to repair mine (in spite of an almost desperate need for it; I have back/hip issues and take my '85 300D on trips regularly; BTW, I'm 99% certain that my amp's what's bad).

My big question is, if one of those aftermarket setups could be installed on a 617 or a 603, could it be adapted to use the stock control setup (the stalk on the steering column)? That would be really cool IMHO...

.

[wolf_walker]

re: aftermarket cruise. Been there done that.

Yes it can use the stock cruise stalk, trouble is most of the vacuum actuators arent strong enough to pull that massive hunk of throttle lincage on these things.

Like I said, if you can stop driving an electric motor directly off a transistor, most of the longevity problems will go away.

That and isolate the module from vibration somehow.

[autozen]

DieselDog,

While you are talking about junky accesories on another wise superior automobile, add the rediculous intermittent wiper interval to the list. The intermittent speed is always wrong for weather conditions and not variable.

Warden,
if you have back problems, that Mb you drive is probably a contributor. You should be driving something like a Toyota for your back. Mercedes makes about the crappiest seats in the world as far as comfort goes. They are very durable though, which you can have mediocre seats for years.

Peter

[Jassper]

Thank you all for your suggestions. After having taken the dash apart a dozen times, pulling the CC amplifier out and putting back in, having it resoldered a few times, I find it the most convenient way will be to order a refurbished amplifier.

The asking price is $89 for internal board of the amlifier, or some $149 I think for the whole lot (alluminium body). I can easily remove the board and have it posted (need to trade in my board to be posted a refurbished one). $89 isn't at all that bad I suppose should the CC be in working condition again.

It's not that I couldn't live without CC. It's just the thought of having it and not being able to use it because it is out of order that makes me want to have it fixed.

Once I used to look forward to take things on my Merc apart, repair them and find out how they work and what they consist of. After years I am just tired and prefer not to take the car apart again and again. Now I know where almost every thing in a Mercedes is and what its use is. Fair enough for someone having studied economics.

I think that some people, when they retire, go fishing to spend time. Or maybe they buy a Mercedes, providing themselves with something to fiddle with and spend time over till they die. Both the fish and Mercedes will keep them busy.

On the other hand Mercedes is a car just like any other. I wouldn't expect any other car of that age to last forever, then why a Mercedes? No car will function perfectly over years, no matter if a Mercedes, BMW, or even a Jugo. The problem is that unlike Jugo, my Mercedes is a classical car with an appealing shape. That is why we invest (money, time and effort) to keep them up instead of simply throwing them away.

Yet, why does my Merc, 12 years old, require so much maintenance? Why am I not to expect that bloody CC to work for at least 20 years? Is 12 years really that unreachable a goal with the manufacturer to ensure that parts will work? Why have I had to rotate the brake disks, readjust and reseal IP, exchange AC evaporator, have a new monovalve, thermostat, new generator, aux. heating pump, engine mounts, flex disks, injectors to mention a few things that come to my mind I had to take care of since 2000 when I bought the car. Not to mention that one the aux. AC fans at the front rotates very hardly and I will have to replace the 2 trans. oil cooler lines also. Why the heck? Why? I am not whining about the car but a Mercedes is certainly no car to kneel down before and pray to. Far from perfect but there is no way around it once you decide you want to own a mint Mercedes.

[The Warden]

Originally posted by autozen
Warden,
if you have back problems, that Mb you drive is probably a contributor. You should be driving something like a Toyota for your back. Mercedes makes about the crappiest seats in the world as far as comfort goes. They are very durable though, which you can have mediocre seats for years.

Actually, every Toyota I've ever been in made things worse. I simply don't fit in them. Also, surprisingly enough, the seat on my 123 doesn't really seem to make things worse by itself; bad as it may be, compared to every other vehicle I've owned (well, except the aftermarket seat I put in my old van; I wonder if I could make that fit in the 300D?), it's probably the best seat I've had to sit on.

It's just something with how I have to move my leg to push the throttle pedal down that makes things worse. In the few times that I've tried the cruise control and it worked, I've always gotten out of the car in much less pain than otherwise.

wolf_walker, you said that "most" of the vacuum actuators can't move the linkage. Does that mean that there are a few that can? If so, which ones? Also, how exactly did you get the aftermarket setup to work with the stock stalk?

Thanks!

[wolf_walker]

I developed the same problem with my back and the little A1 VW's, they were *almost* tolerable on long trips with a working cruise control, and NOT without one. Something about holding preasure with that right leg. I actually found the Mercedes much better, but everyone fits a seat differently.

It's been a long time ago mind you, but as far as I recall I just got a meter and a wiring diagram or the cruise stalk and the aftermarket unit and did some splicing. It's all been removed and patched back up since then, but it worked. When I say *some* are strong enough it's with an air of hope. I know Mercedes used a vacuum actuator before the electric motor setup, perhaps one of those could be utilized somehow, I don't know. I've not given up on the idea, and will get around to digging in it again one day in the not too distant future.

Originally posted by The Warden
Actually, every Toyota I've ever been in made things worse. I simply don't fit in them. Also, surprisingly enough, the seat on my 123 doesn't really seem to make things worse by itself; bad as it may be, compared to every other vehicle I've owned (well, except the aftermarket seat I put in my old van; I wonder if I could make that fit in the 300D?), it's probably the best seat I've had to sit on.

It's just something with how I have to move my leg to push the throttle pedal down that makes things worse. In the few times that I've tried the cruise control and it worked, I've always gotten out of the car in much less pain than otherwise.

wolf_walker, you said that "most" of the vacuum actuators can't move the linkage. Does that mean that there are a few that can? If so, which ones? Also, how exactly did you get the aftermarket setup to work with the stock stalk?

Thanks!

[wolf_walker]

Originally posted by Jassper


The asking price is $89 for internal board of the amlifier, or some $149 I think for the whole lot (alluminium body). I can easily remove the board and have it posted (need to trade in my board to be posted a refurbished one). $89 isn't at all that bad I suppose should the CC be in working condition again.

Who is asking $89 for the internal board only?

[wolf_walker]

Link to aftermarket cruise


Good old J.C. Whitney lists a "custom fit" crusie unit for both electric and vacuum actuator system Mercedes. Pricy, and I bet you'll never get anyone on the phone there that knows what the kit consists of. But it's something..