I just repaired my second cruise control system. Here's what I learned and how I will approach future repair.



Approach #1 Throw money at it. (my 1983 300SD)

Actuator $330
Amp $220
Switch $110

Replace parts in that order until it works. It works great...better than any car.


Approach #2 Take it slow (if you have more time than money). (my 1983 300CD)

Search the forum, find the troubleshooting checklists, use them.
Rebuild your own actuator. (it's working now, but it hunts a bit. I expect to end up buying a new one eventually)
Send your amp out for rebuild. I recently used ProgRama. $125. Works great so far.


Bottom line: this system work great, but may not last as long as you'd like. You may not be able to get it working without buying some or all new components. So, make the decision now: either go without it, or be prepared to go all the way.

Just my opinion...good luck.

Rebuilt your own actuator? I've unsuccessfully tried to do that to a couple of them. I know exactly what parts failed, even, but still can't cobble together a working solution to keep tension on the gears inside to where it won't fly apart under torque.

Link would be pretty good.

I'm looking at replacing my cruise control with an Audiovox vacuum unit, and wiring it up to the stock stalk to keep the original look. The Audiovox vacuum cruise looks a lot like the W116 one also.

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1983 Mercedes-Benz 240D
Automatic, A/C, Power Sunroof, Power Right Side Mirror
231K Miles FOR SALE MAKE OFFER

Sorry, I don't have a link...just figured it out myself.

I drilled out the rivets, then carefully pulled the halves apart. Parts will fly and you have to figure out how to put them back together.

The basic problem was the grease used initially was not high enough temp, and it melted all over the variable resistor contacts, thus shorting out the cruise amp.

So I cleaned everything up (including the motor brushes and commutator) and reassembled using a very small amount of high temp grease.

Like I said, it's working now...for how long, I don't know.

Or, buy an audiovox CCS-100 cruise system and install it....uses the stock switch and everything, will work forever, and its cheap. Also, it maintains the speed just as well.

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-diesel is not just a fuel, its a way of life-
'15 GLK250 Bluetec 118k - mine - (OC-123,800)
'17 Metris(VITO!) - 37k - wifes (OC-41k)
'09 Sprinter 3500 Winnebago View - 62k (OC - 67k)
'13 ML350 Bluetec - 95k - dad's (OC-98k)
'01 SL500 - 103k(km) - dad's (OC-110,000km)
'16 E400 4matic Sedan - 148k - Brothers (OC-155k)

How does the Audiovox work on a diesel if it is vacuum controlled?

Sensor on the driveshaft, then it physically pushes the throttle linkage to keep the RPMs up within the specified range.

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1983 Mercedes-Benz 240D
Automatic, A/C, Power Sunroof, Power Right Side Mirror
231K Miles FOR SALE MAKE OFFER

I see. Yours had a different problem than mine do. The issue in mine is that two tensioning springs, lost their tension -- and now the assembly rotates fine one way, but when rotating the other way, there isn't enough tension to make the gears not slip and grind on each other.

I tried filing down one of the plastic gears to allow the metal plate on the end of the rod that attaches to the throttle linkage to grip both sides but it didn't work out either. And epoxy isn't strong enough.

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1983 Mercedes-Benz 240D
Automatic, A/C, Power Sunroof, Power Right Side Mirror
231K Miles FOR SALE MAKE OFFER

It's been a while since I've had mine open...but, as I recall, hooking the spring onto the case was critical. Are you sure you got yours to hook?

Might try a few from the wrecking yard, since you know how to open them up.

If mine fails, I'll just buy a new one...only so much you can do.

pawoSD,
so, do you just wire in the stock control instead of using the supplied one? Does it just use the vacuum to move the injector linkage? Is it pretty easy to install for a competent home mechanic?
thanks... looks like a great way to get the cruise going!

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1985 300D 170k

I like a variation of approach #1. The switch is easy to test, so it only needs to be replaced if it's bad. A rebuilt amp for $200-300 is a good deal compared to plying around with used ones or trying to repair them yourself. If you are going to replace the amp, install a new actuator to avoid damaging the new amp. For about $600 you can have a perfect system.

3 yard ones and mine later, still no luck :p
the tensioning spring hooks to the spot it's supposed to but it's just so stretched from age that it doesn't apply the correct tension.

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1983 Mercedes-Benz 240D
Automatic, A/C, Power Sunroof, Power Right Side Mirror
231K Miles FOR SALE MAKE OFFER

http://www.peachparts.com/shopforum/showthread.php?t=219993
Just posted this a few days ago...

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Mike
1983 Mercedes-Benz 300SD 270K
1960 Ford F250 62K
1990 Mazda Miata 156k

The thing is Bob, it's not that I'm lazy, it's that I just don't care.

Thats a great write up you did, very detailed.
there is a seller on e-bay AV4MEDOT selling these Audiovox ccs-100.
they range from $87.00 to $114.99 with the vacuum Reservoir for the Diesels. seems the way to go with the problems with the MB cruise.

Charlie ☺

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there were three HP ratings on the OM616...

1) Not much power
2) Even less power
3) Not nearly enough power!! 240D w/auto

Anyone that thinks a 240D is slow drives too fast.

80 240D Naturally Exasperated, 4-Spd 388k DD 150mph spedo 3:58 Diff

We are advised to NOT judge ALL Muslims by the actions of a few lunatics, but we are encouraged to judge ALL gun owners by the actions of a few lunatics. Funny how that works