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2002 CLK430
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Discussion Starter #1
Hello, I'm kind-of new here; been lurking a lot. After looking everywhere for a good way to fix the missing pixel problem in my C208 and not finding an convincing enough method (except a new replacement unit, which would be rather silly), I decided to take mine apart and brain-storm. This is what I found and how I decided to go about fixing it.

The problem with the ribbon connection points in these VDO units, it's in the lousy way they are held together, there is not a single screw holding these things together, it's all tabs. An example of how it should have been done is the center (main) display ribbon connection; it's held down firmly at the circuit board end by a proper connector latch. The ribbons of the smaller screens are glued-on and held-down by small silicone strips, the glue itself is part of the problem as it softens with heat and some residue gets in between the contact points. The pressure exerted by the silicone strips is dependent on the assembly being held together by all the tabs, and it's obviously not enough after a while, so I decided to use screws to provide the clamping force.

This was my first attempt to repair this and I did it rather hastily, nevertheless I am very pleased with the results. I now have a better idea of what to do to ensure a perfect, more permanent fix; for example this is what I didn't do but would if I did this again:

Apply radiant heat to ribbon connection at circuit board to separate it completely, clean it, and reattach it (no glue this time), then spraying some silicone lubricant to keep moisture out.
If you don't want to do this, I recommend spraying the connection with circuit board cleaner prior to going over the ribbon with the soldering pencil.

But, as you will see, the result is rather good as it is. Anyone can do this, it just requires a lot of patience, por example, most people are scared of damaging something when removing the gauge needles, (but damage is more likely if you attempt to pry them straight out), I found that keeping the dust out of the screens and inside of front lens was far more challenging.

Parts used:

(4) Phillips screws (4/32" X 3/8").
(4) Washers (5/16" total diameter). Plastic is preferable but metal ones insulated with tape will work.
Soldering iron (pencil type, do not use pistol type as these heat-up too quickly).
Drill bit (5/64").
Two strips of high density foam (a mouse pad will work) about 1.5" X 5/16"
Mini-screwdriver set.
 

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2002 CLK430
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17 Posts
Discussion Starter #2
When working on electronic circuits such as this, take precautions to prevent static electricity arcing by grounding yourself with a specialised bracelet, Radio Shack sells them cheap. Alternatively, "discharge" yourself by periodically touching the ground as you work along. This is very important, as one single spark can potentially ruin your cluster.











 

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2002 CLK430
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Discussion Starter #3
When re-installing the needles, do not push them straight down. Do this instead:

Position needle at 12:00 o'clock on shaft and gently push down just a bit, just enough so the needle and shaft will spin as one. Spin the needle down to zero and press down simultaneously, tap it down the rest of the way with a rubber-handled screwdriver or other soft object, BE CAREFUL as it is possible to tap it too far and the needle base will contact the dial face. It is a good idea to measure how high the needle sits before removing it (I forgot to add this caption to one of the photos).
From there, you can zero the needle by pushing it towards the zero mark if it sits too high, or spinning it around clockwise and pushing it past the stop if it sits too low. This requires many attempts to achieve, don't worry, those little motors seem to be very sturdy.










 

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2002 CLK430
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Discussion Starter #6
I know it's not very complete. If you have any questions, ask away.

Cheers.
 

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114 Posts
Great post, and Were did you get that steering wheel from? It looks sicks!
 

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2002 CLK430
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Discussion Starter #11
Whats the point of the screws?


See pictures 6 and 7 of post #5

Those tabs are the only thing holding the white assembly and
pressing the ribbons against the circuit board. If you add pieces of
high density foam to increase pressure on the ribbons, these tabs
don't hold, and keep popping out.

The screws take the load off the tabs and exert constant clamping force
on the ribbon connection.

It'll all make sense when (or if) you take the thing apart,
you'll see what I'm referring to.
 

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Ah I see.
Yes I tried the foam last night but only a few different pixels lit up.
How many have attempted this?
Any other success stories?
 

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2002 CLK430
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Discussion Starter #13
I am unaware if someone else has tried it. Some people are intimidated
because these are delicate, precision instruments.

I decided to do it because I got tired of not finding a definitive solution,
it was a gamble, but I'm glad I did.

The important part is to apply heat to the connections as described,
it will also help if you spray some contact cleaner before applying heat.

So far, mine is still working perfectly.
 

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I am going to attempt this tomorrow.
Did you try the foam method prior?

Also I am a little confused about the needle replacement.
Did you have any problems with the speedometer when you placed the needles back on?
 

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Discussion Starter #15 (Edited)
The needles go in about the same way you pull them out, but, as I described it;
tap them the rest of the way down to the correct height, once they're in place
you can start playing with the adjustment, winding them back and forward
until they sit where you want them.

Play with them a little before you remove them so you can feel the "stops"
at zero and all the way around past the 160 mph mark, you push past these stops to adjust them, meaning that you're basically forcing the
needle to slip over the shaft.

I will try to take pictures of the procedure if this is still not clear enough,
I need to replace some bulbs, so I'll be taking my cluster out again.
 

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Discussion Starter #16
Sorry. Yes, I did try the foam by itself first, this is when I found out that
I couldn't keep the tabs engaged, and the clamping force was lousy.
 

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It was a failure.

First the Ribbon came off.
I tried soldering it back on and it wouldn't stay back on.

When it was all done I had the same problem. Even with the foam and the screw.
 
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