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Instrument cluster swap

41K views 26 replies 9 participants last post by  jakewise 
#1 ·
Hello everyone,

I have a '04 c240 i am trying to do a instrument cluster with a clk500 cluster. My car has 94k miles the cluster that i bought has 100k miles, i am wondering if i do the swap now will the odo start displaying again once the car milage reaches 100k?
 
#2 ·
No, it won't "catch up" and start showing the mileage. The cluster must be "married" to the car, which can only be done with a virgin cluster that has no miles on it. This is possible to do with a used cluster, but it requires you to reprogram its EEPROM to zero the miles, then use SDS to adapt the car. There are some (very expensive) tools that can plug in and zero the cluster's mileage. If you are very skilled in micro-soldering, you can remove the EEPROM and use a programming tool (< $100) to zero the miles. Of course you still need SDS to code it to the car.
 
#7 ·
I am not sure which devices will do the zero the cluster. On my C240, I removed the EEPROM and use Carprog to zero the mileage in order to install a used cluster. Check out the forums on Digital Kaos - lots of info there.
 
#9 ·
Just to put this in writing in case it helps anyone, here's my instrument cluster saga:

The cluster problems started with some intermittent shut downs and "twinkling" of all of its lights. This was not just the LCD going bad, as I was aware of that issue, but this was a problem with the whole cluster. It eventually failed completely, so I bought a used one on eBay. After trying several clusters, I discovered that I required one compatible with the old two-wire fuel sender system that my car had, else the fuel gauge would not work. Even though there are programming options in SDS to set the cluster for either sender system, it never worked to set a revised cluster to the older two-wire sender. I read posts where some people who had swapped W209 clusters to the W203 mentioned a wiring change to fix this, but I never found the exact details. I finally just looked for a cluster from a MY2001 with the old part number on it.

Everything worked, but since it was not properly coded to the car, the odometer would read "------". As a security feature, the odometer reading is stored in two places – the EIS (ignition switch) and the cluster. If these do not match, at least within something like 100kms, then the odometer display is blanked out. Only a brand new "virgin" cluster can have its odometer value reset to match the EIS. Since a new cluster was nearly $2,000, I just drove it like this for a few years. I even discarded the original cluster, not thinking that I might need to salvage its EEPROM chip. Besides, the car was being driven by my 16 year-old, so I figured the chances were high that she'd wreck it. Surprisingly, she never did (well, not enough to total it), so eventually, when I titled it to her, we needed the odometer reading.

We don't have vehicle inspections here, but I did have to sign an odometer affidavit and I wanted it to be correct. The odometer reading can be pulled from the EIS, but I could not get SDS to read it. Since SDS worked for other things (ECU/TCU), and worked just find on my CLK, I began to think that this was some sort of designed lock-out since the two odometers did not match. I eventually discovered that the problem was with the MUX on my SDS system. The cheap Chinese part had failed in such a way that it would still work just fine on "facelift" cars (like my MY2007 CLK), but would not work on some systems (cluster, EIS, ACC and SRS) on pre-facelift cars (like the MY2002 C240). I ended up buying a new higher-quality SDS MUX.

I did some research and discovered that if I would zero the odometer value stored in the cluster, then I could use SDS (with a working MUX!) to code it to the car, copying the odometer from the EIS. I talked to a guy at Palo Alto Speedometer and he would do it for about $300 for overnight service. I did more research and found there are tools to do this that plug into the OBDII or the cluster’s connector, but they are expensive (might as well buy a new cluster). Others required de-soldering the EEPROM. I decided to try one of those, so I found one called Carprog on eBay for under $100.

What I needed to do was read the contents of the chip into Carprog, edit the file to set the odometer value to zero, then rewrite the data to the chip. The odometer reading is actually stored twice on the chip – hex range 0000-001F and 0300-031F. Zeroing it means setting the 32 bytes in each of those two ranges to “FF”. I removed the cluster and disassembled it to get to the circuit board. The EEPROM chip is very tiny. It’s an 8-pin SOIC, so it’s less than 5mm long and the leads are less than 1mm wide. In attempting to de-solder the surface-mounted chip, I broke a leg on it. So, I noted the chip part number and ordered a 10-pack of them.

The problem was, I did not have a base program for the chip. The chip from the “used” cluster had a broken leg and I could not read it. The entire chip contents cannot be blank – it needs the base code for the car’s cluster. I found where someone had uploaded the original code from their chip online and used that. I then discovered that the Carprog clip that connects to the chip's leads was improperly wired. After some research there, I got the proper wiring and was able to program a new EEPROM chip with base code and zero miles. Then, when trying to solder the chip back onto the cluster, one of the surface contacts on the circuit board broke loose. I was able to rig it with a jumper wire, though. I mention this to note what a challenge the soldering is. I even used a variable-temp soldering iron, but it’s still a very tedious job, at least for me.

So, with the zero-mile chip in place, the next step was to use SDS to re-code it to the car. I went into cluster programming and used the “initial Startup” option and chose “Initial startup with manual settings input for new control unit (For example: the previous control unit can no longer be read).” This copied the odometer from the EIS and prompted me to input the various settings like national variant and what features the car had or not (KeylessGO, Distronic, NAV, etc.) Once all that was done, the odometer reading was correct and everything was working except for one problem - upon startup, I get this big red warning on the MFD that states "Trasnfer Case LO/HI!" Apparently, the base EEPROM code I had downloaded was for a car with two-speed transfer case, and since my car doesn't have that, it gives this error. Just ignoring it with the steering wheel buttons each time seems to work. I can only assume the EEPROM code I used came from a G-Class as it uses the same cluster as the W203 and it has a two-speed transfer case.

Anyhow, other than the transfer case message, the cluster works fine. I have not had a chance to find a copy of proper base code, but then again, I haven’t spent much time looking. The thought if dealing with that tedious soldering is not very enticing.

I found some really good information on this site:

Digital Kaos

This is where I got the base code and instructions for zeroing the cluster's mileage, as well as discovering that my SDS MUX was bad.
 
#12 ·
Just to put this in writing in case it helps anyone, here's my instrument cluster saga:

The cluster problems started with some intermittent shut downs and "twinkling" of all of its lights. This was not just the LCD going bad, as I was aware of that issue, but this was a problem with the whole cluster. It eventually failed completely, so I bought a used one on eBay. After trying several clusters, I discovered that I required one compatible with the old two-wire fuel sender system that my car had, else the fuel gauge would not work. Even though there are programming options in SDS to set the cluster for either sender system, it never worked to set a revised cluster to the older two-wire sender. I read posts where some people who had swapped W209 clusters to the W203 mentioned a wiring change to fix this, but I never found the exact details. I finally just looked for a cluster from a MY2001 with the old part number on it.

Everything worked, but since it was not properly coded to the car, the odometer would read "------". As a security feature, the odometer reading is stored in two places – the EIS (ignition switch) and the cluster. If these do not match, at least within something like 100kms, then the odometer display is blanked out. Only a brand new "virgin" cluster can have its odometer value reset to match the EIS. Since a new cluster was nearly $2,000, I just drove it like this for a few years. I even discarded the original cluster, not thinking that I might need to salvage its EEPROM chip. Besides, the car was being driven by my 16 year-old, so I figured the chances were high that she'd wreck it. Surprisingly, she never did (well, not enough to total it), so eventually, when I titled it to her, we needed the odometer reading.

We don't have vehicle inspections here, but I did have to sign an odometer affidavit and I wanted it to be correct. The odometer reading can be pulled from the EIS, but I could not get SDS to read it. Since SDS worked for other things (ECU/TCU), and worked just find on my CLK, I began to think that this was some sort of designed lock-out since the two odometers did not match. I eventually discovered that the problem was with the MUX on my SDS system. The cheap Chinese part had failed in such a way that it would still work just fine on "facelift" cars (like my MY2007 CLK), but would not work on some systems (cluster, EIS, ACC and SRS) on pre-facelift cars (like the MY2002 C240). I ended up buying a new higher-quality SDS MUX.

I did some research and discovered that if I would zero the odometer value stored in the cluster, then I could use SDS (with a working MUX!) to code it to the car, copying the odometer from the EIS. I talked to a guy at Palo Alto Speedometer and he would do it for about $300 for overnight service. I did more research and found there are tools to do this that plug into the OBDII or the cluster’s connector, but they are expensive (might as well buy a new cluster). Others required de-soldering the EEPROM. I decided to try one of those, so I found one called Carprog on eBay for under $100.

What I needed to do was read the contents of the chip into Carprog, edit the file to set the odometer value to zero, then rewrite the data to the chip. The odometer reading is actually stored twice on the chip – hex range 0000-001F and 0300-031F. Zeroing it means setting the 32 bytes in each of those two ranges to “FF”. I removed the cluster and disassembled it to get to the circuit board. The EEPROM chip is very tiny. It’s an 8-pin SOIC, so it’s less than 5mm long and the leads are less than 1mm wide. In attempting to de-solder the surface-mounted chip, I broke a leg on it. So, I noted the chip part number and ordered a 10-pack of them.

The problem was, I did not have a base program for the chip. The chip from the “used” cluster had a broken leg and I could not read it. The entire chip contents cannot be blank – it needs the base code for the car’s cluster. I found where someone had uploaded the original code from their chip online and used that. I then discovered that the Carprog clip that connects to the chip's leads was improperly wired. After some research there, I got the proper wiring and was able to program a new EEPROM chip with base code and zero miles. Then, when trying to solder the chip back onto the cluster, one of the surface contacts on the circuit board broke loose. I was able to rig it with a jumper wire, though. I mention this to note what a challenge the soldering is. I even used a variable-temp soldering iron, but it’s still a very tedious job, at least for me.

So, with the zero-mile chip in place, the next step was to use SDS to re-code it to the car. I went into cluster programming and used the “initial Startup” option and chose “Initial startup with manual settings input for new control unit (For example: the previous control unit can no longer be read).” This copied the odometer from the EIS and prompted me to input the various settings like national variant and what features the car had or not (KeylessGO, Distronic, NAV, etc.) Once all that was done, the odometer reading was correct and everything was working except for one problem - upon startup, I get this big red warning on the MFD that states "Trasnfer Case LO/HI!" Apparently, the base EEPROM code I had downloaded was for a car with two-speed transfer case, and since my car doesn't have that, it gives this error. Just ignoring it with the steering wheel buttons each time seems to work. I can only assume the EEPROM code I used came from a G-Class as it uses the same cluster as the W203 and it has a two-speed transfer case.

Anyhow, other than the transfer case message, the cluster works fine. I have not had a chance to find a copy of proper base code, but then again, I haven’t spent much time looking. The thought if dealing with that tedious soldering is not very enticing.

I found some really good information on this site:

Digital Kaos

This is where I got the base code and instructions for zeroing the cluster's mileage, as well as discovering that my SDS MUX was bad.
Hi Rudeney
Your story indeed help a lot as I got the same issue (And many others I suppose).
I am not to clued up on this whole Mercedes Cluster business so my approach might appear somewhat "Clumsy" but please bear with me.
Got some questions.
A. Where on which board sits that chip that needs to be zero'd
B. Quit frankly I blue my old Cluster myself by fiddling with things I should not touch (One learns). It still works but no no more lights and LCD display at all but all others works.
I got a used one (same model and around same year) works but no mileage ---------.
I am tempted to try to fix the ------- by taking out the LCD portion (its a removable unit) from my old cluster and put it in the new one the part numbers are the same bar the last two number. I was thinking that perhaps the mileage data is stored there and by putting the "Old" one in the used/new cluster the mileage "Check' would match and it would show.
Please give me your (and others) your frank opinions on this.
 
#10 ·
@rudeney, I read your write-up with great interest and have some follow-up questions. This is related to a R230 SL55 but I guess it applies to all cars of this era:

1. In SDS under the Instrument cluster menu, we have ‘control unit adaptations’ and the sub-menu ‘Setting main odometer forward and back’. Here you can set it to 0. Should it not be possible to use this command on the new cluster, and then “marry” it to the EIS?
2. If this doesn’t work, can you recommend a speedo shop in the US that can set the used cluster to zero? Palo Alto Speedometers?
3. When I have the used cluster ready to install, I assume I use the ‘Diagnosis to plant specifications’ menu to copy/paste the coding from the old to the new cluster. Do you know of a description of the steps you undertake? Any variant coding necessary? I guess you swap clusters in the middle of the SDS session. But should the negative battery post be disconnected when unplugging/plugging the clusters?

I hope you have the possibility to help me on these questions. I really appreciate it!

(Tried to send you a PM, but your mailbox is full)
 
#11 ·
1. That option to set the odometer forward or backward only works when the mileage on the cluster is 0 - or maybe under 100kms or something along those lines. I think there is a small threshold that allows for brief transport of the car on/off a trailer or moving it around the shop.

2. I contacted Palo Alto, and they said they can zero the cluster's odometer, but I did not use them. Instead, I bought an EEPROM programmer (Car prog "clone") and did it myself on the C240.

3. Don't try to copy from the old cluster. Instead, use the option for installing a new cluster without the old one. It will copy the mileage from the EIS and step you through all the settings.
 
#13 ·
The EEPROM chip that stores the odometer (and all other variables/settings) for the instrument cluster is located on the circuit board that contains the speedometer servo. You have to toally disassemble the cluster to access it. Look here:


The EEPROM is the only 8-leg chip on that side of the circuit board. It's the one in this photo on the bottom left corner:

 
#14 ·
Hey Rudeney! Sorry to bring up this thread, I had a little question for you, you mentioned early on that fitting a w209 cluster on a w203 wouldn't work by swapping Eeproms since these 2 have different chips (actually w209 has a lot in common with the w211 in the EIZ/cluster area). How about swapping post-face lift w203 on pre-face lift w203 ? Could it work by doing an Eeprom swap?
Thank you!
 
#15 ·
That I do not know, but I suspect the EEPROMs are not compatible. However, if you could zero the miles on the post-facelift cluster, you might be able to install it in the pre-facelift car, then use SDS to "marry" it to the EIS. There are some other challenges, though. There were some changes on other parts and the way they communicate over the CAN bus with the facelift. I seem to recall a forum user that some years ago, converted his pre-facelift interior to a post-facelift by replacing all the electronics. It was a huge undertaking and cost him a good bit. I know today's car market is crazy, but I'll bet it would still be less expensive to trace for a psot-facelift car rather than to retrofit these parts.
 
#16 ·
Yes totally understandable. Actually using it as is with the little - - - - - instead of the milage wouldn't be a big issue. It solely for the aesthetics of the newer cluster vs older. I wouldn't mind driving it with those lines but enjoy a nice cluster.
The whole idea is to avoid programming at all. I would simply bring both to an electronic shop and have them swap Eeproms if that resolves the issue of the milage. There would be the concern of having 2 different incompatible chips however. But I think that as long as chip is not ruined by the transfert to a different system, even if it doesn't work, I would switch the chip back to its original cluster and put this idea to rest.
 
#18 ·
Oh yes I understand, I meant for the pre-facelift and post-facelift w203s , if you happen to know I would be glad to try it. The post-face lift w203 is already a major update as long as its Eeprom is compatible with the Pre-facelift
 
#19 ·
No, those EEPROMs are not compatible, either. If you want the odometer to work, You'd have to get someone to zero miles on the new cluster, then use SDS to "marry" it to your car. But there are other things that also may not work. They made major changes to all the car electronics with the MY2005 facelift and when you mix old and new, some things won't work.
 
#20 ·
Thank you Rudeney, understood!!
 
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