So yesterday while driving my beloved W211 on the expressway, I went on to pass a car, kick it down, and by the time the speedometer gauge reached 160 it got stucked, and never went pass 160 kph, although my speed was above 160 according to the digital speedometer. A while later while I was doing 80 kph or so the gauge started working seemingly normal again. But today when I started the car it got stucked at 20kph and never moved ever since.

In the country which I am there is seemingly nobody who repairs these Instrument Clusters, so I attemped the DIY repair by myself before buying another Instrument Cluster.

Step 1: Take the instrument cluster out of the dashboard, and pray on the little tabs that it has both in the upper and lower part to separate the plastic glass cover from the rest.

Upon separating the glass cover, in my case it was clear what had gone wrong. The toothed plastic gear which drives the gauge had cracked and had lost about 1/6th of its teeth. (the red part)



Step 2: Repair it

Sure enough, I could have bought a new plastic toothed gear, they break often and they are available online. however, not in the country in which I am atm, it would have to come either from Europe or China. Which means at the very least 2 to 3 weeks of waiting.

So I decided to torn apart the entire instrument cluster, looking for the missing broken part, and luckily I found it!!

For the rest I just used Loctite SuperGlue to glue it back together. Let it dry for 30 minutes and then used a nail file to eat away the remaining parts of glue and leave it as flat as I could.





Step 3: Assemble it back together & try it.

I put it all back together, fitted it back in the dash. And fair enough I was lucky this time. I don't know how long this repair will last, but I assume that if it cracks again it will be anywhere but the part which I glued, nevertheless I've already order a new toothed plastic gear from China to have as a spare just in case. The gauge is working perfectly fine at the moment, and doesn't jump or get stucked at all not even when going through the part which was glued:

I hope this is useful for someone. Next post I will be replacing the LCD Screen in my cluster for a known good one. As my current has some weird marks on it which are rather uncomfortable to look at



[

mg]https://i.imgur.com/SD9faz[[img]https://i.imgur.com/ztQ0FJ9.jpg]https://i.imgur.com/ztQ0FJ9.jpg5.jpg

 

Good job! And good information for others.

 

do you have the link to the gear part, or the gear's part number? or link to seller?? thank you

 

Very nice OP, where are you from anyway? Wish I was handy but alas I......am not.
Here in states a 'happy ending' has a new connotation these days

 

I bought this exact one:

https://m.vi.aliexpress.com/item/100...640x640Q90.jpg

 

Im European. But located in Thailand atm. Everything here is Japanese, so it’s extremely hard to find Mercedes parts locally, have to order most of them from overseas. That’s really good in order to grow your DIY skills

 

thank you very much, going to order the same for spare parts!!

 

Sawat dee kop! I just got a 3D printer recently and I’m still waiting for an opportunity to use it for something like this. It would be perfect for when you want to fix something right away and it’s not life or death.