Mercedes C Class W203 – Dim Multi-Function Instrument Display (MFD) – LCD Panel Replacement

A Common fault with the Mercedes C Class  instrument cluster is a dimming of the orange LCD multi-function display.  This fading often gets worse when the car is hot or has been out in the sun all day.  The usual places to show the fault are the auto gear selection and W/S icons top right and the lower and upper edge, in some cases totally obscuring any information that may be displayed.  When the car is cold, the display often works better for a time and appears of reasonable contrast only to later fail as temperatures rise.

DSC_1463

Fading Mercedes Display

The LCD unit itself forms part of the instrument cluster and can be removed and replaced.  The negative is that the LCD unit is not available as a spare part (you have to buy the whole console!) The special LCD is manufactured by Motorola (Part number HLM7804) and is common part used in all variants of the C class dash with the arched speedometer and MFD.

Mercedes instrument pod removal

Mercedes instrument cluster removal

Mercedes instrument cluster removal tools

So what to do… Buy a new speedometer (lots of cash) or a used one (incorrect odometer reading)?  Or swap out the display from the cheapest used one you can buy !

To give an idea of the cost of a used instrument cluster from a breakers they are usually about £65 to £95 GB pounds.  The online auction sites are a great source of cheap parts and if you are prepared to scour the listings you will find a bargain. You have the advantage of being able to choose any similar instrument cluster, not bothering about, model year, petrol or diesel types, engine size, 4 or 6 cylinder etc…  This gives you the edge!  Just buy the cheapest you can find.  I managed to pick one up for £30, advertised with a photograph showing the display clearly illuminated still fitted to the car!

UPDATE – It appears there is a company who specialises in the supply of display ribbon cable kits for various MB models here.  Also there is another company, probably in China who can supply the complete W203 display  with bonded cable here (Also other MB and car models it seems)  I have not used either company but I thought the links may prove useful.

Now to replace the display, this is a simple task and can be done with only a length of welding rod, a small screwdriver and some care.

Mercedes instrument cluster removal - welding rod

How the instrument pod latch works

First remove the instrument cluster from the dash, slide down a length of welding rod into the apertures each side of the binnacle, the rod will push onto a moulded latch mechanism, as it is inserted (about 10 cm in) it releases a retaining clasp. Once this is done, hook into the top of the slot a small hexagon key and pull the cluster gently out from the dash, each side at a time.  Set the steering wheel position adjustment – fully out and down to give you maximum working room.

Mercedes C200 Instrument cluster connector

Mercedes C200 Instrument cluster connector

Mercedes C200 Instrument cluster latching connector

Mercedes C200 Instrument cluster latching connector

Draw the pod forward enough to disconnect the multi-pole connector from the rear.  This has a grey lever that has to be unlatched and arced down ward to allow the ‘lever-lock’ removal of the connector. Once this is removed the pod can be slid out of either side of the gap between the steering wheel and instrument cowl.

Mercedes C200 console removed

Mercedes C200 console removed

Make yourself some space and use a soft cloth to put the instrument cluster on.

Carefully release the 2 clips from bottom of the rear of the cluster, pull the cover slightly to just release it from its latches, now do the same with the 3 top clips. The central clip at the top has a warranty label over it that will have to be cut/torn to allow the two halves of the housing to be parted.

Instrument cluster control PCB

Instrument cluster control PCB

Once removed, the back panel can be placed out of the way. Revealed is the main control PCB and orange multi-function ribbon flex connector to the LCD display. This orange flexi-strip is removed from the connector by carefully pushing down the 2 black ears either side, about 1mm, down and away from the connector, this releases an internal clamping mechanism allowing you to withdraw the ribbon flex. Once the flex is released, turn over the instrument pod and remove the instrument chassis from the lens unit.

Remove the LCD flexible connector strip

Remove the LCD flexible connector strip

Grasp each side of the ‘D’ shaped frame that surrounds the display and un-clip it, each side in turn from the front face of the cluster. This will reveal the thin glass LCD display.

Removing the MFD Bezel

Removing the MFD Bezel

Now push up from the bottom edge the LCD glass towards the centre of the dial face, push it just enough to clear the white plastic retaining clips at the bottom, then lever the LCD up and out of the back light holder.

Push back the Motorola LCD unit, then lever up to remove

Push back the Motorola LCD unit, then lever up to remove

The orange LED  illumination area behind the LCD display

The orange LED illumination area behind the LCD display

Strip your ‘donor’ instrument cluster and remove your new LCD unit as described above.  Fit it to your vehicle’s cluster and rebuild it in the exact same manner as you took it apart (again as outlined above) Refit to the vehicle and test.  You should now be able to enjoy a nice bright, high contrast MFD unit !

A nice bright, high contrast MFD display

A nice bright, high contrast MFD display

Just a couple of points to note during this task:  Always make sure that the white loom connector to the back of the cluster is as fully home as possible when re-connecting –  this plug will often engage half way and give the misleading impression that it is fully inserted and all is OK, the lever even moves down to its locked position!  However If it is not fully home the instrument cluster will appear totally ‘dead’ when you turn on the ignition.  Dont panic! just correctly insert the plug, latching it fully home and try again.  The slight downside is, what will have happened when you turned on the ignition with the cluster disconnected, the SRS system will have flagged a fault on its self test (SRS Indicator fault) and will have raised an SRS fault code.  This will have to be reset with a Mercedes OBD scan tool or with the dealer Mercedes Star diagnostic tool. Not the end of the world, but avoided if you make double sure the console plug is correctly inserted before turning on the ignition.

This is a simple, easy fix for a fading MFD and one that can save you a great deal of cash.

31 thoughts on “Mercedes C Class W203 – Dim Multi-Function Instrument Display (MFD) – LCD Panel Replacement

  1. I have problem of my C200 of LED display, totally no sign. Do you have nay person can I contact in Kuala Lumpur, Malaysia

    Regards, yusoff

      1. Hi Steve, tq fr your list of mechanics in Malaysia. Actually, last week I had change the LCD display monitor by new one that ordered from Uk, unfortunately it only working for a few minutes, when i drive the car the LCD is sometimes working and sometimes not, My mechanics said it is due to the failure of cluster software. What is your opinion?

        Regards, Yusoff

      2. Hi Yusoff,
        Its difficult to say what is the problem without seeing first hand the issues. The primary thing to identify is if the illumination LED array at the rear of the pixel panel is failing. Without back light illumination the display will look blank. If all the other instrument function correctly then I would suspect this. Maybe you could look for the regulator circuit that feeds the LED light panel (matrix of orange LEDs) If however there are odd pixels failing and the display is erratic in what it actually displays (strange characters and the back light is ON) then I would look toward the display driver IC circuit to be faulty. There are people that repair instrument clusters, I think you also have the option of replacing the complete unit with a used one. This can be done cheaply, but I am sure that you would have to accept the miles/Km showing on the odometer as that of the donor vehicle – unless you can find some one to change the mileage to that of your old one. The truth is, if you find such a person there is a good chance he can fix your existing instruments anyway! Personally I would check out the power regulators on the PCB if the backlight is found to be intermittent.
        All the best
        Steve

    1. Hi Alvaro,
      If you cannot order the listed parts via mail from the US your best bet would be to purchase a used working speedo (maybe from Ebay) unit and replace the LCD unit as described in my text.
      Good luck.
      All the best Steve

  2. Super easy! Instructions were spot on. I used coat hanger wire to release the tabs. There are suppliers at aliexpress.com That’s were I bought mine shipped DHL express for $110.00

    Couldn’t believe how easy this was to fix. Thank you very much.

    1. This Gen.In follower managed to get one here:
      chris@lostmymail.com
      69.135.203.160

      Submitted on 2014/09/12 at 11:51 pm

      Super easy! Instructions were spot on. I used coat hanger wire to release the tabs. There are suppliers at aliexpress.com That’s were I bought mine shipped DHL express for $110.00

      Couldn’t believe how easy this was to fix. Thank you very much.
      Regards Steve

    1. Hi Christoffel
      If you have no joy with the links in my post and the display cannot be repaired (Poor contact ribbon connection) then I feel your only chance is a unit from a breakers where you can then transfer the LCD unit to your own cluster.
      All the best
      Steve

  3. Hi there,

    Thanks a lot for these instructions. I have followed the links to the aftermarket suppliers and they seem to have the replacement parts for every Merc except the C203. BUT they quote the E and C class in general. I have E Mailed them regarding the W203 C204 model I have but have not received a reply yet.
    Do you know if the unit quoted on their site (C Class) will fit the W203 instrument cluster? I’m from Australia.

    Kind regards
    Chris

    1. Hi Chris,
      You may be able to get a good instrument cluster from a breaker – that is another option, then switch the displays yourself. Ebay could be the route with that method. You would have to be doubly sure what you were looking at from the display guys would fit, as it would be just throwing money away if it were not 100 per cent compatible. Wait and see what they say, send them a photograph of the cluster (ignition on) if you need to.
      All the best
      Steve

  4. Hi Steve,

    I just replaced the lcd screen in two w203s and the process went smoothly, as you describe. I got the screens from the firm in Italy, by the way.
    My own car was fine straight away. My friend’s car started fine but then, a short time later, maybe half an hour, parts of the screen were dark and remains so after some weeks. I contacted the Italian supplier giving the sysmptoms and they said that thier screen was obviously fine and that the fault must lie with the leds that backlight it.
    The leds are visible when you remove the led screen but do you have any idea about replcing them?
    All the best
    Ed

    1. Hi Ed,
      When the console is powered do all the LEDs in the backlight matrix illuminate? As you describe it, it really sounds as if the display is faulty, even though they deny it possible. Best bet is to take a series of photographs and show them the issue including a photo of the backlight matrix fully working! – Then perhaps you will get some where with a replacement.

      To replace the LEDs is a huge undertaking, as they are all surface mount components and its not an individual assembly. They are soldered on to the mother board itself. Plus they are very reliable by their nature and I am still doubting the fact they are faulty. You could always pop the original old LCD or your old one back in to prove the point – don’t forget to take photos to send to Italy!

      Hope that helps,
      All the best
      Steve

      1. Dear Steve,
        Many thanks for the prompt and very helpful advice. I’ll try to see if the leds light up by plugging the intrument cluster in without the lcd screen in place.

        Regards

        Ed

      2. Hi Ed,
        Once you have ascertained that all the LED’s in the matrix are illuminated, I would test it again with the diffuser in place (LCD Removed), that way you will be able to get an idea of the uniformity of illumination across the display backlight area. I still think it’s an LCD issue, but let’s give him the benefit of the doubt!
        All the best
        Steve

  5. hi steve, i have a c180 automitic MB about 3-4 year old. The intrument cluster is lit light orange and display no letters/numbers are shown on the intrument.
    Can you please adive if the ribbon cable is he probelm

    regards
    Dee pat

    1. Hi Dee,
      I would think the ribbon is the issue, it generally is. I will admit its unusual to lose all the display but is very possible. Best bet is to try and get hold of a cluster and swap the LCDs over. If not and it turns out to be the cluster you have a difficult job on your hands as the replacement unit has to be programmed to the vehicle and milage corrected to match that in the ECU or else it displays ——– instead of a miles reading on the oddo. Chances are its the LCD, nothing more.

      All the best
      Steve

  6. Hi Steve,
    I have bougth a used c200 Kompressor w203 1.8 litre. The dashboard light of “CHECK ENGINE” no came ON when the ignition key switch to on position. The others warning lighst came all ON . I have scanned the car with OBDII Scan tool and the result is MIL status ON and P0172 DTC code detected. But the “CHEK ENGINE” lamp is alweis OFF. It is posible a action of delear for desactived the lamp warning indicator of “CHECK ENGINE”? For camuflage defect of car? It Is posible set OFF status for mean of DAS diagnostic programming?
    Thank a lot in advanced for your opinion

    1. Hi Paolo,
      The M271 engine has an issue with the PCV hose (crank case ventilation hose and non/return valve) What happens is that due its location it gets a great deal of heat and in time degrades splitting and allowing unmetered air into the throttle body often causing lumpy idle an over rich mixture DTC code P0172. I suspect this is your issue. As the engine tries to compensate for the unusual air condition it does not always flag the Check engine lamp. In some instances it is stored as a pending code or frequently one that is reset on each start cycle. I would be very surprised if this was not the issue. MB did actually do a recall on this part on some early models as it was quite troublesome.- If left unattended, it has been rumoured to accelerate the variable timing gear wear as the engine advances to compensate for the issue – I have seen no direct evidence of this from a verified source, but seems entirely possible and my own experience has shown the PCV hose fault to exist on the few engines that I have seen with cam chain failure.
      There is some detail of these small hoses here

      I hope this helps and I can say that the function of the engine check lamp cannot be defeated unless the led has been cut from the dashboard cluster (rather like this on a commercial model) or blanked behind the indicator with black insulating tape – Highly unlikely if purchased from an Approved Mercedes Benz franchise.

      Often if you leave the petrol tank cap off you will get a CEL lamp after a short while as the system uses a pressure sensor to detect the correct fitment and sealing of the fuel tank. As you have a code reader you could replace the petrol cap with a temporary push in one, drive a few miles and see if the check lamp illuminates, you can confirm this alarm with the code reader, resetting and refitting the correct fuel cap when you have proved the correct lamp function.

      Hope this helps,
      All the best
      Steve

      1. Hi Steve
        thanks fo the accurate and comprehensive diagnosis!. I also understand the risks that this hole leak problem may result to the cammes engine fault…. My OBDII scan tool show my always an almost constant voltage of 1.48 – 1.51 V from the O2 sensor precatalyst at hot engine idle running!!!!!… instead of 0.2 – 0.9 V !!!!. My code engine is M271.940 203 042 1.8 Litre of 2003 Year. Here in Paraguay unfortunately the mechanicians and delaer do not have a good skill level!!! and do not speak the english language….. Please can you gently give me the exact mercedes spare code number of the “offending” hole ? Thanks a lot. About the failure of the CEL light, i bought the c200 Kompressor from a local multi-brend used cars seller, not from a Approved Mercedes Benz seller… This car has been imported directly from japanese used market and it has 65,000 Kilometer. I will try to perform the petrol tank cap off and let you know the result.
        One thing i wont you to know, when the ignition key is in the position 2 (dashbord ON and ENGINE OFF ) all the warning check light came ON (SRS light, BRAKE light, DTR light, BLUE Hight head light etc. etc.) , The only one light that does not came ON is the yellowo of the “CHECK ENGINE” warning !!!! Strange…. I read on a forum that can be set permanently light off trought the DAS STAR diagnostic in ADVANCED PROGRAMMING MODE… on the instrument cluster OPTIONS SET…It my be true in your opinion?

        Thanks a lot for his alwais professional and valuable answers!!!!
        Paolo Loretoni

      2. Hi Paolo,

        Part numbers as follows:

        Vent Hose: A 271 018 12 82
        You should also replace the 2 hoses below the Kompressor.
        Hose: A 271 018 15 82
        Check Valve: A 271 018 03 29
        Hose: A 271 018 14 82

        The ‘check valve’ that connects the two lower hoses together I think the part is A2710180329 ( you will have to check out the valve part number to be sure, but I think that is correct) You can see the vent hose configuration here, in reality it is just visible if you remove the air box and look down the one inch gap between the supercharger and the engine block. Once the air box is totally removed you can just about access the hoses. Make sure you get hold of a large size ‘jubilee clip’ to replace the spring-type clip on the intake pipe from the air box. Unless you have the correct spring clip tool, you will struggle to get this back on. A screw type hose clip of the appropriate size makes life easier!

        While I suppose it could be possible to defeat the engine check lamp with some computer high level hack, I am pretty sure as it forms among other things, part of the stringent emissions warning system I am almost sure it can’t be bypassed simply – but who knows!

        Hope the above helps.

        All the best
        Steve

  7. Hi Steve,
    my best compliments for your preparation and knowledge of the mercedes engines!!!!!
    I’m a retired former italian computer tehnician that now i live in the Paraguay and i understend when a person speaks knowingly or not…. he he… I would have to tell how many stupid things i’ve heard here…
    unfortunately… Okay, Now i have to try to find on the “bay” the various spare parts and then start the job.. I”ll keep you updated when i finish!!!
    A really biiig thank you Steve!!
    Ciao
    Paolo

  8. Do you think it is possible for a faulty LCD to kill all instruments in the cluster?

    Our LCD dimmed over a few years and now the whole cluster is dead (no gauges work at all)

    Thoughts?

    DC

    1. Hi Denis,
      It sounds more likely to be either a supply fuse, cabling, connector or internal voltage regulator. I doubt the LCD panel unit itself could cause such a problem.
      Best Steve

  9. Display Backlighting

    In fact I agree with Steve, I have been doing tests and realized reparation on circuit board powers of the LEDs.

Leave a Reply to Steve Ball Cancel reply

Your email address will not be published. Required fields are marked *