Frequently Asked Questions

How do I ship a cluster to you?

Here is a checklist to use when shipping to us :

  • Package the cluster well! The following picture depicts a good packaging container filled with shipping popcorn for a typical cluster. A good place to find a suitable box is your local grocery store. Rummage around the empty boxes, empty biscuit boxes work best, which are roughly 50cm X 30cm X 30cm. The cluster should additionally be wrapped in bubble plastic for added protection. It is up to you to safeguard your cluster, so please package it well! Front lenses are very fragile, easy to crack, and expensive to replace.

    Make sure the cluster has enough stuffing to keep it from moving around and has at least an inch of stuff between it and the cardboard. If you feel secure enough to drop it from waist height onto a concrete floor, it's ready for shipping. After all, that will be the treatment it will be given when it's out of your hands. Be sure to place a "this side up" and "FRAGILE" sticker on the box, provided by the staff.

  • Canadian customers need not worry about cross-border/brokerage fees. USA and other international customers must deal with border issues. Please note : Only your country's Federal Postal Service can be used for shipping! Example, USPS for the United States, and Royal Mail for the UK. Private couriers like FedEx, UPS, DHL and Purolator do not recognize repair and return shipments and must not be used, otherwise heavy duties will be incurred!

    The MBCluster repair service is a special type of cross-border transaction called a repair and return or R&R. The Canada Border Services Agency must be informed that the unit will be repaired and returned, has no commercial value, and thus have no applied brokerage fees. Canada Custom's way of keeping track of these R&R shipments is by using a special database that is expected to be accessed again when the package leaves the country. To properly describe the package as an R&R transaction, these steps must be precisely followed:


    1. Get a box, pack the item well, then weight it and measure it! Don't forget to include the Repair Form with return address information inside.

    2. For international customers, customs needs the following Commercial Pro-Forma Invoice. It must be filled out in triplicate (print 3 of them) and attached to the package in a zip-lock bag. This invoice can be downloaded here :

    3. Place the following information clearly on the box in large lettering. (Its easiest to print it on the back of one of your Pro-Forma pages)


      When you are finished, your shipping box should look something like the following. (Shipping label on top comes next).

      International/US shipment, with From, To and Fragile labels (shown from left to right) International/US shipment, with Shipping label, and Pro-Forma documents (shown from top to bottom)

    4. For those with access to online shipping tools from their PC, access your Federal post office site online, otherwise go to your local post office. Customs forms need to be filled out when shipping to another country. In the USA, a form CP72 is used, which is available at the post office when you are ready to send your package. When filling out the form, use the following information in the areas shown:

      Insure for $500
      (Insured value)
      Other: NCV-R&R
      Value is $1
      (Declared value)
      Made in Canada
      (To comply with NAFTA)

      Putting $1 as the declared value is very important, as that is the declared value, it has no commercial value, it is not for sale. It will be returned to you shortly after the repair is complete. It does have, however, insured value, in the case of loss or damage by the post office, which is very rare.

      The address to send to is :

      James Kouramanis
      8 Blacktoft Drive
      Scarborough, Ontario
      M1B 2M6 CANADA

How do I remove the cluster?

For the W140, it's not too difficult, with great care you can do it yourself. Mercedes sells these pull hooks to accomplish the job #W140 589 02 33 00:

You can also buy inexpensive hooked tools at the local hardware store. Paying careful attention not to damage the housing or the leather surrounding it. It is very, very easy to crack the corners on the housing, so be careful! Sometimes its easier to work with both hooks from one side to get it to give. If you are applying more than a couple pounds pressure, leave it to a professional to remove, or take the alternative approach.

This housing was damaged when removed, a $400 replacement item!

There are two possible ways to remove the cluster: the fast way which is more prone to damage and is chosen by MB mechanics; and the slow way which is more labor intensive, but nearly guaranteed not to break. Here is a step by step of the fast way:

  1. Adjust the steering wheel fully down and towards you.
  2. Remove the keys from the ignition, and disconnect battery.
  3. The cluster has "ears" molded along the sides where the manufacturer intended the hook tool to grab on to. Turns out this method was prone to damage and is now considered an incorrect tugging point! Instead, you must grip the instruments from nearer to the rear, catch a flat spot and tug from there. Ensure your tool is at least halfway buried before attempting to pull or else slippage and breakage is certain! Over the years, the instruments have been seated snugly inside the leather surround, so this will be certainly laborious.

    The following are pictures of various R129/W140 instruments through the years, red arrows indicate incorrect tugging points, blue indicate correct :

    1992-1994 W140 analog instruments

    1994-1997 W140 digital instruments

    1989-1992 R129 analog instruments

  4. There will be just enough room, once the cluster is out of its hole, to slide it around. Carefully manipulate it with enough room to slide your hand behind and start removing the harness connectors. There will be 4 of them. Pay close attention not to pull them out by the wires. The rounded connector can be pulled by hand. The square connector has a small tab sticking out which you must use your hook tool to pry out.
The slow way, but the way recommended for most first timers, is as follows :
  1. Remove all of the sound deadening panels under the dash (above the pedals), and the ventilation ducting. There are two hidden clips, located on both lower sides of the steering wheel, holding the lower knee-bar, which can be removed by applying a screw-driver tip to the release lever, as shown below.

  2. Reach inside and push the cluster out from behind. This is a tremendously awkward position, you must crank your arm in all the way and push out with vigor.
  3. There will be just enough room, once the cluster is out of its hole, to slide it around. Carefully manipulate it with enough room to slide your hand behind and start removing the harness connectors. There will be 4 of them. Pay close attention not to pull them out by the wires. The rounded connector can be pulled by hand. The square connector has a small tab sticking out which you must use your hook tool to pry out.
  4. Replace the ducting and the sound panels, as the installation is done from the front.
This will take longer, but if you're fearful of damaging anything, it's the safest bet.

Installation is simply done by reconnecting the electrical connectors and gently easing the cluster back into its hole. It should easily snap into place.

For older Mercedes models, removal instructions can be found here :

What if my cluster ends up not being the problem?

It's not usual, but entirely possible that the problem you're seeing in the cluster is actually upstream. Logically there are only a few real possibilities :

The problem could be a simple issue or a more serious vehicle electrical malfunction, or even possibly both. It's not unheard of to have a crack in the wiring harness, causing the problem. Its rare, but even possible that an electrical issue has fatally affected the instruments, and an instrument repair without finding the root problem would only cause another fatal instrument malfunction later on! Siemens has since recalled the older manual odometer design which is very sensitive to its environment and replaced with an all digital, and more forgiving cluster. Here are some steps to try to exclude the vehicle from being the source of the problem :

  1. First check the fuses! On older models, it's not un-common for the fuse contact surface to corrode due to bi-metallic contact. You'll have to yank them out, scrape the surface, and reseat. Fuse location for early W140 is on fuse box #3, and according to the (140) fuse designation, check fuses 17, 23, 24. Especially for early S/SL owners complaining of instrument malfunction when using turn signals or wipers, this can be traced down to corroded fuses. All fuses, especially fuse #9 must be checked and cleaned. Even if they look undamaged, closer inspection usually reveals weak points, all fuses should be replaced. R129 and earlier Benzes now have the option to upgrade all fuses to brass/copper ceramic fuses, which do not have bi-metallic issue, available here. The early(129) fuse designation can be found here.

    Nearly unnoticeable, this early R129 fuse is indeed faulty
    Copper contacts and aluminum ceramic fuses cause corrosion

  2. The cluster itself has a self-test diagnostic feature, which can be accessed via the clock knob on the right. The information is quite useful for debugging sensor information and general instrument health. To use it, start the engine, depress the centre of the knob for 5 sec., then extend and twist the knob clockwise. Each twist increments the test number ranging from 1 to 9, as described below. To exit test mode, turn the car off.

    Depress knob centre with pen

    1992-1994 W140/R129

    1994-1997 W140/R129

    • Test mode 1: Fuel tank contents in liters

    • Test mode 2: Momentary fuel consumption in liters/hour

    • Test mode 3: Engine oil pressure in bars

    • Test mode 4: Engine RPM

    • Test mode 5: Engine oil level (e.g. 0 indicates OK and 1 indicates Not OK)

    • Test mode 6: Gauge override - 1/4 gauge position

    • Test mode 7: Gauge override - 2/4 gauge position

    • Test mode 8: Gauge override - 3/4 gauge position

    • Test mode 9: Gauge override - 4/4 gauge position

  3. For models W140 and R129, 1991-1996, the instruments' electrical harness can be checked. Using a digital multimeter (only), a few important signals can be probed on the harness connectors. NOTE: Do NOT use a mechanic's trouble light, as this feeds back power, and may cause damage! IF you do not have electrical experience or are uncomfortable checking, skip this step or seek the help of an experienced electrician! Be very careful not to short any signals to ground! The following pins are seen from the perspective of the harness ends :



    • Set multimeter and test leads for DC Voltage check (Max. 20V).
      Use grounding harness bolt (pictured above) for reference ground.
      Check for constant good positive (12V) on pin 2.12.

    • If pin 2.12 is correct, use it as a constant good reference positive (12V).
      Check for good ground (0V) on pin 1.10.

    • Put the keys in the ignition and turn them slowly until the fuel pump turns on (do not start the car).
      Use grounding harness bolt (pictured above) for reference ground.
      Check for good constant positive (12V) on pin 1.1.
      Check for good constant positive (12V) on pin 1.5.
      Activate turn signals and remeasure, ensuring voltage is stable.

    • If pin 1.1 is correct, use it as a constant good reference positive (12V).
      Check for good ground (0V) on pin 2.11.

    WARNING: Do NOT attempt to connect wires to the harness or introduce voltages to them! Irreparable harm may result to your vehicle! Only licensed Mercedes dealers can work on the electronics of your vehicle! Do not attempt to connect voltages to the instruments, as they are very sensitive and susceptible to total failure with incorrect or mis-timed voltages! A burnt wiring harness or power surge to any ECU will result in permanent vehicle and electronics damage!

    To print out these instructions, click here : printer friendly version.

    If the voltages seen on the multimeter do not match those expected above, the vehicle is most likely at fault. If the voltages appear correct, yet strange behavior is observed such as instrument failure when riding over potholes, or cold weather causing problems, this may be another indication the vehicle is at fault. Unfortunately, there is no further debugging that can be done, and the Mercedes dealer must be consulted.

If everything seems to point to the cluster, then send it in and we'll check for you. If we can't find a problem with the cluster, then the problem is still with the car. No harm done, we wont charge you anything for the diagnosis. All you need to do is pay for the shipping to get it back to yourself.

Are European and American clusters interchangeable?

American Cluster

European Cluster
European (metric) and American clusters are pin-compatible. As long as the entire cluster is swapped in your car, it will function normally. The differences between the two types of clusters are :
  • Temperature LCD is Fahrenheit for American, and Celsius for European
  • Odometer and trip are miles for American, and KMs for European
  • Speedometer face is dual for American, and only KMs for European
  • Economy gauge is MPG for American, L/100 KMs for European
The circuit boards alone cannot be swapped, as they are not interchangeable. The American circuit board will drive MPG and Fahrenheit so the gauge will need to be MPG and the LCD Fahrenheit.

Are the W140s and the R129s interchangeable?

Absolutely not! Although they appear to be identical, and they will fit in each respective car, the operation would be incorrect. Here are the differences :
  • W140 gas tanks are 100 L, R129 are 80 L. The fuel gauge reading would be incorrect.
  • Transmissions have gearing before the VSS, which means that 320, 500, and 600 clusters are designed specifically for their application. The replacement instruments need to be engine matched.
  • R129 VSS and tach signals have negative voltage biases, which cause misreading from W140 clusters.
As a result of the uniqueness of the R129 cluster, it is a more difficult unit to find second hand.

What taxes do you charge (for Canadians)?

Each province in Canada has its own tax scheme, they are not all uniform. Some pay PST, GST, RST or HST. The following map depicts the tax layout for Canada :

2013 Canadian Provincial Tax Map

As a business registered in Ontario, MBCluster charges tax depending on the province the customer is located. If it is out of province, the customer will be charged the GST or HST rate based on where the goods are being shipped to.

Therefore, if it is B.C., the charge is 12%, in Ontario, Newfoundland and Labrador, or New Brunswick, the charge is 13%, to Nova Scotia 15% and if it is Alberta, Manitoba, Saskatchewan, Quebec or Prince Edward Island, the Northwest Territories, Nunavut or the Yukon, the only charge is 5% (the GST rate).


How do I know if my odometer gear is broken?

If your odometer or clock is not turning as it should, a broken gear may not necessarily be the cause of the problem. As newer odometers are electrically driven, an electrical fault may be the source of the problem. Burnt driver chips, or dried capacitors are often times the root cause. Symptoms of these electrical faults are excessive battery drain when resting, or general inaccuracy.

Although, not to say that gears are seldom the issue, as they are simply made of vinyl, and prone to the caustic effects of petroleum products such as grease over time. Typically, though, cars from hotter climates, such as the southern states like California, or Hawaii will be prone to broken odometer gears due to the excessive heat. Unfortunately, it is impossible to say whether the gear is broken or not without disassembly. The following are examples of broken gears:

W126 with broken vinyl gears
W140 with broken vinyl gear
W124 with odometer gear slipped off shaft

If the gear is indeed broken, a fresh set is available from a large and reputable US supplier located in Virginia. The specific gear will depend on being applicable for metric or imperial use, and will require a careful and precise gear count. The specifics of the gear measurements can be found here:

New gears from

MBCluster deals exclusively from this supplier, and we can order the gear once your instruments are received and diagnosed. Shipping times are usually a week, no extra stock is kept on hand, as the specific gear varies with application.

Why do people replace the 140/129 wiring harnesses?

During the years 1990-1994, beginning from the introduction of the new 129/140 models, Mercedes decided to deploy a soy-based wire sheathing for its wiring harnesses. After a short time, they discovered that this material was highly biodegradable and prone to premature failure. After MY 1994 they returned to the industry standard polymer based sheathing material for all models.

All harnesses within the 1990-1994 129/140 models are susceptible to premature failure, although fortunately, due to the moderate ambient in-cabin conditions, most of the interior harnesses tend to not fail. The issue predominantly affects the engine compartment harnesses, which have the more aggressive hot and cold engine conditions. This is the reason why many forums and mechanics will usually recommend replacing the engine harness as a first line of defense against electrical issues.

To see if your harness is in certain need of replacement, closely inspect your engine wiring harnesses to see if they are showing signs of failure similar to the images pictured below:

The implications of a deteriorated wire sheathing range from infrequent electrical glitches to all out catastrophic failure. According to the U.S. National Highway Traffic Safety Administration, several complaints have been recorded regarding electrical hazards. This link is a transcript of some consumer complaints.

Email :

MBCluster | 8 Blacktoft Drive | Scarborough, Ontario, Canada | M1B 2M6 | (416)724-2149 | Email :

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