MB Medic Mercedes-Benz Repair Guides, Service, How To DIY
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This article will show you how to remove the instrument cluster. How to fix problems with dead, dark, or flickering S-Class W220 instrument clusters. Repair display defective issues on the Mercedes-Benz S-Class W220 and CL-Class C215. Mercedes-Benz ran a campaign for this exact failure. NHTSA lists it as 06V028, covering model year 2000 through 2006 S-Class and CL-Class cars, chassis 220 and 215, and it extended the instrument cluster warranty from 4 years or 50,000 miles out to 10 years with unlimited miles from the warranty start date, regardless of who owned the car. Two things worth knowing about it: 1998 and 1999 cars fell outside the campaign, and since coverage ran 10 years from the warranty start, every W220 is now past it. It is still worth running your VIN through the NHTSA recall lookup, because open recalls on other systems are repaired free of charge no matter how old the car is.
This article will list the most common problems with this cluster and solutions. You can try these repairs yourself. If these repairs seem too complicated, read our alternative solution in the conclusion section at the end of the article.
These instructions apply to:
S-Class: 1998-2006 S430 S500 S600 S55 AMG
CL-Class: 1999-2006 CL500 CL600 CL55 CL63 AMG
In this guide (5 sections)
How to remove the cluster from a Mercedes-Benz S-Class or CL-Class
To repair this cluster, you first need to remove it. Removing the cluster from a Mercedes-Benz S430/S500/CL500 is easy. To remove the cluster, you will need the following tools:
Work with the battery disconnected. The cluster sits on the car’s data network, and unplugging a live module is how you store faults you then have to go and clear. Give it a few minutes after disconnecting before you start pulling trim in the dash.
- Disconnect the negative battery terminal and wait a few minutes.
- Slide the hooks of the removal tool into the slots at each side of the cluster face until you feel them engage the retaining clips.
- Pull straight out and evenly on both sides. The cluster comes forward as a unit. If you pull on one side at a time you will cock it in the opening and crack the lens or bend the housing.
- If the right side refuses to release, do not lever harder. Take out the center air vent and press that holding clip in by hand, then pull again.
- Once it is forward, support the cluster with one hand. Do not let it hang on the harness while you work on the connector.
- Release the lock on the electrical connector and lift it off. Pull on the connector body, never on the wires.
A word on what not to use: prying the cluster out with a screwdriver is the method that ruins the bezel and the dash trim around it, and jigsaw blades in place of the proper hooks are an improvisation that works right up until one slips. The tool is inexpensive and it is the difference between a clean job and a scratched dash.
On reassembly the cluster pushes back in until the clips seat. Your mileage and settings are held in the cluster, so nothing is lost by removing it, but check for stored faults afterward and clear them if the car logged the disconnect.
Watch the removal on video
Remove Cluster W220 S-Class from DIYCarCenter.com on Vimeo.
Common problems with the S-Class and CL-Class instrument cluster
The instrument cluster on the Mercedes-Benz S-Class uses LEDs and fluorescent tubes to illuminate and backlight the gauges. It is common for the cluster to start flickering and eventually completely burn out. This is the failure behind the 06V028 campaign described above, and that coverage has now run out on every one of these cars. When the cluster fails, it commonly takes out its own fuse, listed as F79 in the fuse assignments. A completely dead cluster with a blown F79 is the classic presentation. Confirm the rating against the fuse chart for your own car before you replace it, and if a fresh fuse blows again straight away, stop swapping fuses, because something on the board is pulling it down.
MOSFET
For this repair, you will need the following:
- N-Channel MOSFET Transistors (two BUZ102S and one BUZ102SL)
- T12 Torx Driver
- Soldering Iron
- Desoldering Braid
This instrument cluster carries three MOSFETs, which are metal oxide semiconductor field effect transistors used here as power switches. Check the part numbers before you order, because they are not all the same: the board takes two BUZ102S and one BUZ102SL, so a set of three identical transistors leaves you one short of the right part. Two common signs of the transistors failing are a blown cluster fuse and a transistor that has come away from the board and is rattling loose inside the housing. To replace them, follow these steps:
- Remove the instrument cluster.
- Unplug the electrical connector from the back of the instrument cluster.
- Remove the black plastic housing.
- Remove the screws that hold the circuit board using a T-12 Torx socket. Carefully release the plastic tabs using a flat-blade screwdriver.
- Replace all three N-Channel MOSFET power-switching transistors.
High Voltage Transformer
The other component that fails in this cluster is the high voltage transformer, and if you are diagnosing rather than following a known-good diagnosis, start here rather than with the transistors. The transformer is the more common culprit of the two, so testing or replacing it first often saves you desoldering three transistors that were never the problem. One caution on parts: cheap replacement transformers have a reputation for failing again not long after they go in, so this is a poor place to save a few dollars.
Treat the board as static sensitive. MOSFETs are damaged by static discharge you will never feel, so ground yourself before handling the board and hold it by the edges. The transformer is a high voltage part, so let the cluster sit unpowered before you work on it, and do not probe the transformer with the cluster powered up.
To complete this repair, you will need the tools mentioned above, plus the following:
S-Class Instrument Cluster Transformer
Instructions on replacing the transformer.
- Remove the instrument cluster.
- Unplug the connectors near the rear of the cluster.
- Separate the cluster instrument housings.
- Remove the gauge needles from the instrument cluster. You can remove them by pulling them out.
- Remove the LCD message screen.
- Remove gauge trim.
- Unsolder the fluorescent lamps and any LED lights on the way.
- Access the circuit board and replace the defective transformers. Fluorescent tubes
The high-voltage fluorescent tubes, which create the illumination and the backlighting for the cluster and gauges, fail over time. They may flicker and eventually die. You could replace the fluorescent tubes or even replace them with 12-Volt LED lights connected in series and feed. If can learn how to do this hack by watching this video here.
Repairing yours versus fitting a used cluster
A used cluster from a breaker looks like the cheap way out, and it is the one route on this job that carries a legal catch, because the mileage belongs to the cluster rather than to the car. Federal law is specific about this. Under 49 U.S.C. 32704, if an odometer is repaired or replaced and the reading cannot be kept the same, it must be set to zero and a written notice stating the previous mileage and the date of the work has to be attached to the left door frame, and removing or altering that notice with intent to defraud is itself prohibited. Separately, 49 U.S.C. 32703 prohibits altering an odometer with intent to change the mileage it shows. So a donor cluster showing someone else’s miles is not something you can quietly leave in the car and forget about, and it will come up again when you sell.
Repairing your own cluster sidesteps all of that, because the odometer never changes. That is the practical argument for fixing the board rather than swapping the unit, quite apart from the cost.
Conclusion
Hopefully, these instructions helped you to repair the instrument cluster on your Mercedes-Benz. But these repairs may not be for anyone, and we understand if you don’t want to damage your instrument cluster even more. So what is the solution? Use an online service. Specialist companies offer mail in repair for your instrument cluster. These repairs won’t break your bank account; all your instrument cluster settings, including the mileage, remain the same. Here is the service we recommend.
Module Medics instrument cluster repair
Need some help diagnosing a problem in your Mercedes-Benz? Use a YOUCANIC Scanner to fix your car like a pro!
Helpful Articles
- Mercedes-Benz Instrument Cluster Recall
- MBCluster – Mercedes S-Class W220 Lighting Repair / LED Upgrade
Before you buy parts, scan every control module, not just the engine. It shows the root fault behind the warning lights and tells you whether the problem is still active. See how to do a full health check.
