Mercedes Instrument cluster pixel failure repair
**HQ SILVER cable with VIDEO repair manual **
Several Mercedes models, including C Class and E Class from 1995 to 2003 have fading or completely dead pixels on the instrument cluster LCD display. This display normally shows the mileage, the temperature or the clock.
This missing pixel failure is very common at the following types:
E-Class W210 (1995-2002) : E200, E220D, E240, E280, E290TD, E300TD, E320, E420, E430
C Class W202 (1995-2000) : C180, C200, C220, C230, C270, C280
CLK Class W208 (1997-2009) : CLK55 AMG, CLK200, CLK230 kompressor, CLK320, CLK430
The pixel problem lies with the ribbon cable that connects the LCD display to the circuit board of the instrument cluster. The pictures below show the instrument cluster's LCD display before and after the ribbon cable replacement (just an example of several board computer / dashboard instrument cluster types):
1. Mercedes C Class Instrument cluster - Manual and Automatic Gearbox:
The instrument cluster on the picture below is a common Mercedes-Benz C class speedo, with automatic gearbox. To repair the speedo DIY, you need 3 ribbon cables, and some cases a set of bulbs to get the speedo back to normal working order. The easiest way to make sure you buy the right set of ribbon cables if te LCDs on your speedo look like the one on the picture, you are buying the right set of ribbon cables. This particular instrument cluster has 3 LCD's:
- outside temp display
- mileage displays
- time + gear display
2. Mercedes E Class (2000+) Instrument cluster - assembled with 3 LCD on it:
The instrument cluster on the picture below is a common Mercedes-Benz E Class (2000+) however was also used some cases at C Class models too. This particular instrument cluster has 3 LCD's, but the set contains only 2 ribbon cables, as the big one in the middle is normally not failing. The content of your set is:
- outside temp display flexible cable
- time + gear display flexible cable
3. Mercedes E Class (from 1995-1999) Instrument cluster - assembled with 1 BIG LCD in the middle:
The instrument cluster on the picture below is a common Mercedes-Benz E Class (1995-1999). This particular instrument cluster has 1 LCD display in the middle, which is failing after a couple of years of use. Typicall fading pixels, missing LCD lines, or completely dead LCD display - one can fix / repair this LCD failure with ribbon cable replacement. This is a heat sealable ribbon cable design, which means you need to solder the cable to the panel with a special heat sealing T-head. This T-head is also available, and can be used on several soldering iron models.
4. Mercedes Vito CDI pixel failure, gauge failure, or completely dead unit:
Well this speedometer has several typical failures.
- LCD display pixel failure: if the LCD display pixels are fading, the ribbon cable needs to be replaced. This repair can be done DIY. You will need a T head for soldering the new ribbon cable.
- Speed and RPM gauge pointers do not move, stick in different positions, do not show the real value. This case the gauge motor housing needs to be replaced. Fix can be done DIY.
- Fuel level and temperature pointers show false value. To repair this failure you need to replace the complete gauge motor.
- Completely dead unit. This is very typical, that the speedometer doe not work at all, but when warms up it starts working. This case you need to replace the main processor MC68HC908AZ60 2J74Y of the unit. This is not a DIY repair job, soldering and IC programming involved.
4. Mercedes A class pixel failure:
At this model the most typical failure is that the LCD dispay pixels are fading, missing, or the LCD is completely dead. This case you need to replace the fauty ribbon cable. This repair can be done DIY, however you will need a T head for soldering the new ribbon cable.
Why do the Mercedes speedometer LCD displays fail with pixel failure? DIY Pixel repair helps with pixel failure? Well the Mercedes speedo manufacturers have a few minurtes only to produce a complete Mercedes speedo with LCD dispay and silver or carbon ribbon cable. Because of this, VDO Instrument Cluster manufacturer decied to assemble the Mercedes LCD display and the silver / carbon ribbon cable with heat bonding procedure. This Mercedes speedometer assembly design makes the contacts of the LCD display and the ribbon cable loose contact very fast, most cases in just a few years. This means, the Mercedes LCD display show pixel failures, it needs pixel repair, but both the silver ribbon cable and the Mercedes LCD display work well - only the connection of them is bad, that is why you have LCD display pixel problems, and you need a pixel fix by a professional, or done DIY with an LCD display pixel repair KIT - a silver or a carbon cable. How can we improve the quality of the LCD displays and the ribbon cables? Well if you assemble the Mercedes LCD with the ribbon cable with pressure, no heat bonding, then the pixels of the LCD display will work for an unlimited time. Dashboard LCD displays work on high temperature, so it is the best to avoid using the heat bonding procedure. Pixel repair DIY, or pixel fix by a professional?
The LCD display repair ribbon cable KIT is available in silver cable and in carbon cable version. Once the Mercedes dashboard instrument cluster LCD display pixel failure was properly repaired, the Mercedes speedometer display will work as new, the silver ribbon cable and the LCD will work for good in the speedometer.
I replaced the silver ribbon cable of the unit, but still there is nothing on the instrument cluster display's screen:
No worries, this symtom can be due to a bagatel problem which is easy to fix. If there are no pixels on the Mercedes instrument cluster display at all, that MUST be due to one of the followings:
- the contacts of the instrument cluster display or the panel are not perfectly clean - this case there is no contact between the Mercedes display and the panel
- either the Mercedes instrument cluster display or the silver ribbon cable was mounted in the wrong direction, so the contacts are on the wrong side
- the alignment of the silver ribbon cable is no good, so the pads of the silver ribbon cable do not match the pads of the Mercedes instrument cluster LCD display or the panel.